Material requirements: sizes, durations, formats
On a first post you do not stumble over strategy or pricing but over the clip being the wrong length, the image the wrong weight, and the text cut off mid-sentence. Every platform has its own requirements, they live in different corners of the help centre and change without notice.
Here they are collected from the platforms' own documentation, with a link and a check date. We do not take «size cheat sheets» from other sites: there are plenty of them, and they go stale silently.
Where a limit depends on conditions, we say so. On some platforms clip length depends on account verification, file weight on the subscription, and the number of images on the catalogue section. We will not pick one case for you.
Aitu
Text length. The limits are announced in the description of the message sending method: the text of a message — "max 4096"; the name of the sender (sender.name) — "string max 100"; the title of a button, the body of a button and the text shown to the user — "max 100"… the limits are taken from the validation column in the description of the sendMessage method of the business interface; the documentation sets no separate limit for the caption to media source, checked 2026-08-04
Images. The documentation does not set formats and a size for an image directly. From the list of kinds of files: "the mimetype of the file: unknown, jpeg, mp4, m4a, mp3, gif, png". For the "share an image" method the encoding is stipulated: the image "Must begin… the formats are derived from the list of mimetypes and not from a separate requirement; the "share" method — https://docs.aitu.io/aituapps/aitu.apps/methods/shareimage.md source, checked 2026-08-04
Video. There are no separate requirements for video. Video appears as a kind of content ("The type of content: document, image, video, audio, music") and as the mp4 mimetype. The documentation names neither a codec, nor a resolution, nor a size, nor an aspect ratio… the platform returns the properties of a file, but sets no requirements for it source, checked 2026-08-04
Audio. Audio is set apart into separate kinds of content — audio and music, the mimetypes m4a and mp3, and for both the duration is returned in the response. The documentation sets neither a bit rate, nor a sampling rate, nor a maximum size audio on this platform is an independent kind of material, but there are no numerical requirements for it source, checked 2026-08-04
Upload limits. A file is uploaded by a separate request in the multipart/form-data format, and its size is returned in the response, but the documentation names no maximum size. A mailing limit is announced: "The maximum number of recipients per request is 300", and… the file size limit is not published; the limit of 300 is about the number of recipients per request, not about the number of files source, checked 2026-08-04
Bluesky
Images. источники расходятся: "Each post contains up to four images, and each image can have its own alt text and aspect ratio". The limit on the file size of a single image is named twice and differently on one and the same page: in the text — "Individual images are limited to 1,000,000… the source contradicts itself: in the text 1,000,000 bytes, in the code example on the same page 2,000,000 bytes with a reference to the same schema; the limit… source, checked 2026-08-04
Video. "Bluesky currently supports .mp4, .mpeg, .webm, and .mov video files", "Each post can contain one video". The platform names neither a codec, nor a resolution, nor a bit rate, nor a frame rate. The upload goes either the usual way (uploadBlob to one's own… the formats are announced in a blog entry of 11 September 2024; the platform does not publish technical requirements for the video file; the order of the upload… source, checked 2026-08-04
Video duration. источники расходятся: The source contradicts itself. The blog entry about the launch of video (11 September 2024) says: "Videos can be up to 60 seconds long". A later blog entry (26 January 2026) proceeds from a different limit, three times as large: "three-minute videos aren't… 60 seconds is the launch page, three minutes is https://bsky.social/about/blog/01-26-2026-whats-next-at-bluesky ; the platform has no separate help centre page with the number in force, and both blog… source, checked 2026-08-04
Upload limits. The limits are given separately by level. An attachment: "The PDS also applies a maximum size limit on individual blob uploads... The current limit is 52,428,800 bytes (50 MByte)". The number of videos per 24 hours: "Currently, you can upload 25 videos / 10… the limits depend on the level (the storage instance, the video service, the app) and on the confirmation of the email; the network is an open one, and the platform writes directly that other… source, checked 2026-08-04
Discord
Text length. The text of a message — "Message contents (up to 2000 characters)". The limits of a formatted embed are set separately: the title 256 characters, the description 4096, the name of a field 256, the value of a field 1024, the text of the footer 2048, the name… 2000 characters is the limit named by the developer documentation; the raised limit for the paid subscription is not described in it, and the help centre support.discord.com is closed by a Cloudflare check source, checked 2026-08-04
Images. A sticker: "the sticker file to upload, must be a PNG, APNG, GIF, or Lottie JSON file, max 512 KiB", "Uploaded stickers are constrained to 5 seconds in length for animated stickers, and 320 x 320 pixels"; Lottie stickers are available only to servers with the… the Lottie format depends on the status of the server; on emoji — https://docs.discord.com/developers/resources/emoji ; there are no requirements for ordinary pictures in the documentation source, checked 2026-08-04
Upload limits. "The maximum request size when sending a message is 25 MiB". Per message: "Up to 10 rich embeds (up to 6000 characters)", "IDs of up to 3 stickers in the server to send in the message", and in allowed_mentions no more than 100 role identifiers and 100 user… a user's file size limit depends on the subscription (a free account, Nitro Basic, Nitro), but the official support.discord.com article about attachments is closed by a Cloudflare check, so the… source, checked 2026-08-04
Gap
Text length. The developer documentation does not name limits on the length of text (a message, a caption, the description of a file): there is no number of characters for the text sending method or for the desc field when a file is uploaded. The only announced limits on… our translation, the original is in Persian and English; the limits of 10 KB and 1 KB are about game data, and not about the text of a message source, checked 2026-08-04
Images. Only the recommended formats are set, without dimensions and file size (our translation): in the file upload table the "فرمت پیشنهادی" column (the recommended format) for the image field contains "jpg, png, jpeg". The documentation names neither a resolution… our translation, the original is in Persian; the formats are called recommended ("پیشنهادی"), and not mandatory; the general file size limit is in the upload_limits row source, checked 2026-08-04
Video. Only the recommended format is set (our translation): for the video field — "mp4 (h264 baseline)", that is, MP4 with the H.264 codec in the baseline profile. The documentation names neither a resolution, nor a frame rate, nor a bit rate, nor a separate file size limit for video our translation, the original is in Persian; the codec is named in the column of recommended formats, and not as a requirement source, checked 2026-08-04
Audio. Audio is divided into two kinds, and each has its own recommended format (our translation): the voice field (a voice message) — "ogg", the audio field (an audio file) — "mp3". The documentation sets neither a bit rate, nor a sampling rate, nor a duration our translation, the original is in Persian; a voice message and an audio file are different kinds of attachment on this platform source, checked 2026-08-04
Upload limits. The limit on the size of an uploaded file depends on the kind of bot and on the method of sending (our translation): "ربات تعاملی" (an interactive bot) — "50 مگابایت", that is, 50 MB; "ربات اطلاع رسانی" (a notifying bot) when sending "فردی" (to one person)… our translation, the original is in Persian; the limit directly depends on the kind of bot and on whether this is a personal sending or a mailing source, checked 2026-08-04
imo
Images. The only announced requirement for an image is the resolution by default: "On imo, 1080P is the default resolution, offering the perfect balance of sharpness and smooth performance on most screens", and moreover "We minimize compression to preserve the"… 1080P is called the value by default, and not the maximum; the choice of HDR is an editing setting, and not a requirement for a file source, checked 2026-08-04
Images. image: JPEG format, «8 MB maximum», aspect ratio that «must be within a 4:5 to 1.91:1 range», width from 320 to 1440 pixels Adds numeric bounds to the existing jpeg_only fact source, checked 2026-07-28
Video. video: duration from 3 seconds to 30 minutes, a file from 75 KB to 500 MB, MP4 format; captions — one file per video and only in English A CONTRADICTION IN THE SOURCE: the description of the fileSizeBytes field on the same page says «Maximum allowed Videos size is 5GB» source, checked 2026-07-28
Mastodon
Text length. источники расходятся: "The main body of each status update can be composed using the text field. The default character limit is 500 characters" — 500 characters are named as the value by default, not as a hard limit. Links are counted at a constant length: "All links are counted… the platform is not a single service but a program for individual instances, and almost all the numbers are configured by the owner of the instance: the documentation names them as values by default… source, checked 2026-08-04
Images. "Images (PNG, JPG, HEIF, WEBP, AVIF) up to 16MB. Images will be downscaled to 8.3 megapixels (enough for a 3840x2160 image). Up to 4 images can be attached, per post". An animated GIF is counted separately: "Animated GIFs (GIFV) up to 16MB are converted to… the platform is not a single service but a program for individual instances, and almost all the numbers are configured by the owner of the instance: the documentation names them as values by default… source, checked 2026-08-04
Video. "Videos (MP4, M4V, MOV, WebM) up to 99MB. Video will be transcoded to H.264 MP4 with a maximum bitrate of 1300kbps and framerate of 120fps. Only one video can be attached, per post". In machine form: "video_size_limit: 103809024" bytes… the platform is not a single service but a program for individual instances, and almost all the numbers are configured by the owner of the instance: the documentation names them as values by default… source, checked 2026-08-04
Audio. Audio is an independent kind of attachment: "Audio (MP3, OGG, WAV, FLAC, OPUS, AAC, M4A, 3GP) up to 99MB. Audio will be transcoded to MP3 using V2 VBR (roughly 192kbps). Only one audio file can be attached, per post". The list of accepted types in the… the platform is not a single service but a program for individual instances, and almost all the numbers are configured by the owner of the instance: the documentation names them as values by default… source, checked 2026-08-04
Upload limits. The file size of an attachment: an image and a GIF — "up to 16MB", video and audio — "up to 99MB"; in machine form "image_size_limit: 16777216" and "video_size_limit: 103809024". The number of attachments in a post: "max_media_attachments: 4", and at the same… the platform is not a single service but a program for individual instances, and almost all the numbers are configured by the owner of the instance: the documentation names them as values by default… source, checked 2026-08-04
MAX
Text length. The documentation does not name a limit on the length of the text of a message, of the caption to an attachment or of a post in a channel. Only the limits connected with buttons are announced: "For a button of the link kind the maximum size of the link is… the number of buttons in a row depends on their type; the platform does not publish the length of the text itself either in the developer documentation or in the help centre https://max.ru/help Quoted text is our translation from Russian. source, checked 2026-08-04
Images. An image attachment: "Available formats: JPG, JPEG, PNG, GIF, TIFF, BMP, HEIC", "The maximum size of one image: up to 50 MB or no more than 7680 x 7680 px — both criteria must be met. For example, it is not possible to send an image of 55 MB and 7600 x 7600… the two conditions for an image act together, and not by choice — the source directly stipulates this with an example; the requirements for stickers… source, checked 2026-08-04
Video. A video attachment: "Available formats: MP4, MOV, MKV, WEBM", "The maximum size of one video: up to 250 MB". The documentation names neither a codec, nor a resolution, nor a frame rate, nor a bit rate. A video message is a separate kind of entry, it is… the limit of 250 MB relates to an attachment sent through the bot interface; in the help centre for people it is put more softly — "attachments of up… source, checked 2026-08-04
Video duration. The limits are given separately by kind of entry. A video message: "The maximum duration of one video message is 60 seconds". For an ordinary video attachment the documentation does not name a limit on the duration — the restriction is only by file size (up… 60 seconds is the limit precisely of a video message recorded in a chat, and not of an uploaded video file; the limits of attachments — https://dev.max.ru/docs-api Quoted text is our translation from Russian. source, checked 2026-08-04
Audio. Audio is an independent kind of attachment: "Available formats: MP3, WAV, M4A and others", "The maximum size of one audio: up to 256 MB or of a duration of no more than 60 min — both criteria must be met. For example, it is not possible to send audio of a… both conditions act together, the source explains this with an example; about a voice message — https://max.ru/help/messages/kak-zapisat-audiosoobshhenie Quoted text is our translation from Russian. source, checked 2026-08-04
Upload limits. источники расходятся: The numbers are different for a person and for a bot. The help centre for people: "You can send in messages attachments of up to 4 GB each: photographs, videos, files of different formats, contacts and location". The developer documentation sets the limits by… the source contradicts itself: the help centre for people promises "up to 4 GB each" directly for photographs and videos, while the developer documentation on the same day sets an image 50 MB and a… source, checked 2026-08-04
Live streaming. The platform has no live streams of its own, and therefore it does not publish requirements for a signal either: "Broadcasts in a MAX channel are a live stream format that you launch in VK Video, while the publication for the channel in MAX you create with… the requirements for the signal itself are set by VK Video, and not by MAX; the order of creation — https://max.ru/help/bots/kak-sozdat-translyacziyu-v-kanale-max Quoted text is our translation from Russian. source, checked 2026-08-04
Mercado Libre
Text length. источники расходятся: There is no number of characters for the title and the description of a listing on the documentation pages checked. There is a requirement as to the form of the description: "The description must be in plain text", "Remove HTML tags, emojis, or special… the source contradicts itself: the description page requires plain text without markup, while the frequently asked questions… source, checked 2026-08-04
Images. "The maximum size we accept is 1920 x 1920 px (F version) and the minimum is 500 x 500 px (M version)"; "If the image has higher resolution, it will be resized for version F", "If the image is smaller than the minimum, it will be the same size (we will not… the minimum of 500 x 500 px is counted after the white margins have been cut off — the platform warns that the margins are removed with an allowance of 10% source, checked 2026-08-04
Video. A clip for a product: "Format: MP4, MOV, MPEG, or AVI", "Maximum file size: 280 MB", "Minimum resolution: 360x640 pixels", "Vertical video". In the hint to an error the codecs are named: "use common export settings, like MP4 with the H.264 video codec and AAC… the codecs are named in the hint to an error and not in the list of requirements — this is a recommendation, not a prohibition source, checked 2026-08-04
Video duration. "Duration: minimum 10 seconds, maximum 61 seconds" — from 10 to 61 seconds both bounds are declared source, checked 2026-08-04
Upload limits. The number of images depends on the product branch: "There are um maximum images per item allowed to publish according to the category", and the error reads "Items in category … cannot exceed X pictures". The images of product variations are counted as well… the limit on the number of images depends on the product branch, the platform publishes no single figure; the daily limit for clips — https://global-selling.mercadolibre.com/devsite/working-with-clips source, checked 2026-08-04
Text length. The limits are the same for an image and for a video and are given separately by field: the title — "100 characters max", the text on the material itself (textbox) — "250 characters max", the description — "Enter up to 800 characters". For advertising the… the limits are separate by field, not a general one for a post; the advertising provisos about 40 and 30 characters — https://help.pinterest.com/en/business/article/pinterest-product-specs… source, checked 2026-08-04
Images. источники расходятся: An ordinary pin: "File type BMP, .JPEG, .PNG, .TIFF, .WEBP", the maximum file size depends on the device — "Web: 20 MB maximum", "Android and iOS: 1 GB recommended". The safe margins: "Top: 270 px, Left: 65 px, Right: 195 px, Bottom: 790 px". An advertising… the limit on file size depends on the device and on the kind of pin, and the source contradicts itself: for a mobile the help centre on pins has "1 GB recommended", while the help centre on… source, checked 2026-08-04
Video. An ordinary video pin: the formats depend on the device — "Web: .MP4, .M4V", "Android and iOS: .MP4, .MOV, .M4V"; "Video encoding H.264 or H.265". The aspect ratio: "For full-bleed videos... we recommend using a 9:16 ratio or 1080x1920 pixel size. Other… the set of formats depends on the device of the upload, the file size is announced only for advertising; the table of containers and codecs — https://help.pinterest.com/en/business/article/pinterest-product-specs source, checked 2026-08-04
Video duration. The limits are different for an ordinary video pin and for advertising. A video pin: "Video length Minimum 4 seconds, maximum 5 minutes". An advertising video: "Minimum 4 seconds, maximum 15 minutes", and at the same time "Recommended length for video ads: 6 to 15 seconds" the lower limit is common (4 seconds), the upper one depends on the kind of post: 5 minutes for an ordinary pin against 15 minutes for advertising… source, checked 2026-08-04
Audio. The platform has no independent upload of an audio file: in the list of kinds of pin there are only an image and a video. Requirements for audio are announced only as part of the table of permissible codecs for an advertising video — AAC, MP3, PCM, AIFF… audio exists only as a track of a video; the permissible audio codec depends on the container and is not set by a single list; https://help.pinterest.com/en/article/review-pin-specs was also checked… source, checked 2026-08-04
Upload limits. File size: an ordinary pin — "Web: 20 MB maximum", "Android and iOS: 1 GB recommended"; an advertising image — "Desktop 20 MB, In-app 32 MB"; an advertising video — "Up to 2GB"; a carousel image — "20 MB per image". The number of materials at a time: "2 to 5… the rate limit depends on the app's level of access (Trial or Standard) and on the category of the call; the numbers themselves — https://developers.pinterest.com/docs/reference/rate-limits/ ; the… source, checked 2026-08-04
Qiita
Text length. The help centre does not name a limit on the length of the title and of the text of a post. Other numbers are announced (our translation): tags per one post — "1つの記事には最大5個までのタグを設定できます" (no more than 5), and at the same time "タグを1個以上設定する必要があります" (at least one… our translation, the original is in Japanese; the platform does not publicly limit the length of the title and of the text; the number of drafts — https://help.qiita.com/ja/articles/qiita-post source, checked 2026-08-04
Images. An image in a post (our translation): the formats "avif, gif, jpeg, png, tiff" are supported; one file — "単体で10MB" (up to 10 MB); in total per month — "月に合計100MB" (up to 100 MB); the recommended width for display in a post is about 800 pixels. The user's icon… our translation, the original is in Japanese; the monthly limit of 100 MB is the total volume of uploads, and not the size of one file; the icon — https://help.qiita.com/ja/articles/qiita-profile-image source, checked 2026-08-04
Upload limits. The limits on the uploading of images (our translation): "単体で10MB" per file and "月に合計100MB" per month; the monthly counter and the deletion of files are on the settings page qiita.com/settings/upload_images, and moreover what has been deleted is not restored.… our translation, the original is in Japanese; the monthly limit on volume depends on the calendar month, and not on the plan; the frequency of requests — https://qiita.com/api/v2/docs (the platform's… source, checked 2026-08-04
RUTUBE
Images. The channel cover image: "Use for this a picture in .jpeg format of no less than 2204 × 826 pixels and weighing no more than 10 MB". The picture of a broadcast: "For correct display the picture (preferably in JPEG format) must have an aspect ratio of 16:9 or… the format of the broadcast picture is called preferable, not obligatory; the source is https://rutube.ru/info/faq/ Quoted text is our translation from Russian. source, checked 2026-08-04
Video. источники расходятся: "formats: MP4, AVI, WMV, MOV, FLV, MPEG-1, MPEG-2, MPEG-4, MPG, MPEGPS, 3GPP, WebM, DNxHR, ProRes, CineForm, HEVC (H.265)"; "audio codec: MPEG 2 AAC-LC, Stereo"; "video parameters: bitrate above 3600 kbps, a resolution up to 3840 X 2160 (an aspect ratio of… the source contradicts itself: WMV stands both in the list of permitted formats and in the list of formats it advises avoiding Quoted text is our translation from Russian. source, checked 2026-08-04
Video duration. "duration: no more than 5 hours (300 minutes)". The help centre names no minimum duration the limit is one for everyone and does not depend on the type of account — the help centre stipulates nothing else Quoted text is our translation from Russian. source, checked 2026-08-04
Audio. The platform has no separate audio format: audio is described only as the track of a video — "audio codec: MPEG 2 AAC-LC, Stereo". At the same time the help centre mentions that a user may upload "ready-made video clips and podcasts", but gives no separate… podcasts are named, the requirements for them are not described separately Quoted text is our translation from Russian. source, checked 2026-08-04
Upload limits. "size: no more than 25 GB" per video clip. The help centre names no number of files at one time. A clip becomes published after a check: "usually this happens within 24 hours" the size limit is announced, the limit on the number of files at a time is not Quoted text is our translation from Russian. source, checked 2026-08-04
Live streaming. "Recommendations for the broadcast stream: Quality: HD/FullHD/2K/4K; Codec: H.264; Frame rate: up to 30 fps; Video bit rate: 4-6 mb/s; Audio codec: MPEG 2 AAC-LC, Stereo; Audio parameters: bitrate 128 kbps, 44100 KHz". The reservations: "in the current… the name of the protocol is not given on the page, although the broadcasting is described through OBS; the frame rate for a live stream (up to 30 fps) is lower than for an uploaded file (60 fps) — these are different requirements, not an error Quoted text is our translation from Russian. source, checked 2026-08-04
Snapchat
Text length. The caption to material passed from a third-party application (Creative Kit): "Captions are limited to 250 characters" — 250 characters, the same for a photo, a video, a sticker and a lens. The text fields of an advertisement are set separately: "brand_name… the limits depend on the path of publication: 250 characters is about passing from a third-party application, the other numbers are about advertising… source, checked 2026-08-04
Images. Passing from a third-party application (Creative Kit): "Images must be PNG or JPEG", "Shared media must be 300 MB or smaller", "Suggested aspect ratio 9:16". A sticker separately: "A static sticker must be PNG or JPEG", "File size 1 MB or smaller"; a moving… the limits are given separately by kind of attachment and are different for publication and for advertising; the web formats… source, checked 2026-08-04
Video. Passing from a third-party application: "Videos must be MP4 or MOV", "Shared media must be 300 MB or smaller", "Suggested aspect ratio 9:16". Uploading through the web: "540x960 minimum resolution", "Snapchat content has a 9:16 aspect ratio", the platform… the requirements are different for passing from an application, for a web upload and for advertising; the web… source, checked 2026-08-04
Video duration. The limits are different by kind of publication. Spotlight from the application: "Create a video Snap that's 5 seconds or longer" — no shorter than 5 seconds. Uploading through the web (a story and Spotlight): "Videos must be 5 to 60 seconds long" — from 5 to… the limit depends on the method of publication, the platform has no single figure; the web — https://help.snapchat.com/hc/en-us/articles/7012310003348-How-to-Post-a-Snap-to-My-Story-from-the-Web… source, checked 2026-08-04
Upload limits. Passing from a third-party application: "Shared media must be 300 MB or smaller"; a sticker — "File size 1 MB or smaller" and "Only one sticker allowed per share". Uploading advertising material: "32MB max size, up to 1 GB allowed using chunked upload", and… the limit of 1 GB is attainable only by uploading in parts, in one piece it is 32 MB; the advertising limits — https://developers.snap.com/marketing-api/Ads-API/media ; the platform does not publish a daily number of publications source, checked 2026-08-04
SOOP (AfreecaTV)
Live streaming. There are numbers only in the old guide for streamers, and they are called recommended. The setting for high-quality broadcasting from a television board (an article of 14 January 2009): "비디오 인코더: 640*480" — the encoder 640x480; "화질: 1000K" — the quality 1000… our translation, the original is in Korean; the numbers are given for broadcasting from a television board and in the source are marked as recommendations, not… source, checked 2026-08-04
SoundCloud
Audio. "Accepted source formats include: AIFF, WAVE, FLAC, OGG, MP2, MP3, AAC, AMR, WMA". The uploaded file is not given to listeners as it is: "After a successful upload the track is queued for encoding; listeners stream transcoded output (for example AAC), not the… the list of formats is named as an approximate one ("include"), and the platform keeps the canonical list on the Upload Requirements page, which is closed by protection from robots; there are no… source, checked 2026-08-04
Upload limits. uploading: up to 4 GB per file and up to 24 hours of audio per track; the rules are the same for the API and the interface The Key Facts section of the API documentation source, checked 2026-07-28
Upload limits. The file size and the duration of a single upload: "each upload may be up to 4 GB and 24 hours of audio in length", and the same numbers are repeated in the short list: "Upload limits: up to 4 GB per file and 24 hours of audio per track". Calls to the API are… 4 GB and 24 hours are the limit for a single upload, the same for the API and for uploading from the site ("same rules for API and in-app uploads"); it was not possible to check the dependence of the… source, checked 2026-08-04
Telegram
Text length. The limits are given separately by kind of entry (Bot API): the text of a message — "1-4096 characters after entities parsing"; the caption to an attachment (photo, video, audio, document, voice) — "0-1024 characters after entities parsing"; the caption to a… the figures are taken from the Bot API documentation — this is the only place where Telegram publishes them numerically; there are no limits on the length of text in the help centre telegram.org/faq source, checked 2026-08-04
Images. A photo in a message: "The photo must be at most 10 MB in size. The photo's width and height must not exceed 10000 in total. Width and height ratio must be at most 20". When uploading by link the limit is lower: "5 MB max size for photos", when sending… "width and height must not exceed 10000 in total" — the sum of the sides, not each side; for a story the size is set rigidly and not as a minimum source, checked 2026-08-04
Video. A video for a story (InputStoryContentVideo): "must be of the size 720x1280, streamable, encoded with H.265 codec, with key frames added each second in the MPEG4 format, and must not exceed 30 MB". For an ordinary video in a message the documentation sets no… the codec and the resolution are set rigidly only for stories; the user's file size limit — https://telegram.org/faq source, checked 2026-08-04
Video duration. A story video: the duration field is described as "Precise duration of the video in seconds; 0-60", that is, no longer than 60 seconds. The lifetime of a story is set by the active_period field and "must be one of 6 * 3600, 12 * 3600, 86400, or 2 * 86400"… the duration is announced only for stories; for ordinary videos the platform does not limit the duration but limits the size source, checked 2026-08-04
Audio. Audio is a separate format with two kinds. A music file (sendAudio): "Your audio must be in the .MP3 or .M4A format", "Bots can currently send audio files of up to 50 MB in size". A voice message (sendVoice): "your audio must be in an .OGG file encoded with… the limit of 50 MB applies to bots; for a user the general file limit of 2 GB (4 GB with Premium) applies source, checked 2026-08-04
Upload limits. The user: "Send and receive files of any type, up to 2 GB in size each (or 4 GB with Premium)" — the limit depends on the Premium subscription. The bot: "Bots can currently send files of any type of up to 50 MB in size"; when sending by an HTTP link — "5 MB… the limit of 2 GB / 4 GB depends on the Premium subscription; the bot's limit of 50 MB is from https://core.telegram.org/bots/api , where it is also stipulated that "this limit may be changed in the future" source, checked 2026-08-04
Threads
Text length. a text post is no more than 500 characters; emoji are counted by their number of UTF-8 bytes, so one emoji «eats» several characters of the limit Important for schedulers: the length calculation does not match the usual character count source, checked 2026-07-28
Text length. "Text posts are limited to 500 characters", and moreover it is not characters that are counted but bytes for part of the symbols: "Emojis are counted as the number of UTF-8 bytes". The topic of a post is set by a separate field with a limit of its own: "Topic… the platform's own domains (www.threads.net and www.threads.com) directly forbid ClaudeBot in robots.txt ("User-agent: ClaudeBot / Disallow: /"), and the help centre help.instagram.com does too; the… source, checked 2026-08-04
Images. images: JPEG and PNG are officially supported; maximum width 1440 (anything larger is downscaled), sRGB colour space source, checked 2026-07-28
Images. "Format: JPEG and PNG image types are the officially supported formats for image posts", "File Size: 8 MB maximum", "Aspect Ratio Limit: 10:1", "Minimum Width: 320 (will be scaled up to the minimum if necessary)", "Maximum Width: 1440 (will be scaled down to… the platform's own domains (www.threads.net and www.threads.com) directly forbid ClaudeBot in robots.txt ("User-agent: ClaudeBot / Disallow: /"), and the help centre help.instagram.com does too; the… source, checked 2026-08-04
Video. video: MOV or MP4 (MPEG-4 Part 14) container, no edit lists, moov atom at the start of the file A requirement about the structure of the file, not just its format source, checked 2026-07-28
Video. "Container: MOV or MP4 (MPEG-4 Part 14), no edit lists, moov atom at the front of the file", "Video Codec: HEVC or H264, progressive scan, closed GOP, 4:2:0 chroma subsampling", "Frame Rate: 23-60 FPS", "Picture Size: Maximum Columns (horizontal pixels)… the platform's own domains (www.threads.net and www.threads.com) directly forbid ClaudeBot in robots.txt ("User-agent: ClaudeBot / Disallow: /"), and the help centre help.instagram.com does too; the… source, checked 2026-08-04
Video duration. "Duration: 300 seconds (5 minutes) maximum, minimum longer than 0 seconds" — the lower boundary is set not by a number but by the condition "longer than zero" the platform's own domains (www.threads.net and www.threads.com) directly forbid ClaudeBot in robots.txt ("User-agent: ClaudeBot / Disallow: /"), and the help centre help.instagram.com does too; the… source, checked 2026-08-04
Audio. The platform has no independent upload of an audio file: "media_type... Values: TEXT, IMAGE, VIDEO". Requirements for audio are set only as for a track of a video: "Audio Codec: AAC, 48khz sample rate maximum, 1 or 2 channels (mono or stereo)", "Audio… the platform's own domains (www.threads.net and www.threads.com) directly forbid ClaudeBot in robots.txt ("User-agent: ClaudeBot / Disallow: /"), and the help centre help.instagram.com does too; the… source, checked 2026-08-04
Upload limits. File size: an image — "File Size: 8 MB maximum", a video — "File Size: 1 GB maximum". The number of materials in a post: "You may publish up to 20 images, videos, or a mix of the two in a carousel post", "Carousels require a minimum of two children"; at the… the platform's own domains (www.threads.net and www.threads.com) directly forbid ClaudeBot in robots.txt ("User-agent: ClaudeBot / Disallow: /"), and the help centre help.instagram.com does too; the… source, checked 2026-08-04
TikTok
Video. video through the Content Posting API: MP4 (recommended), WebM, MOV containers; H.264 (recommended), H.265, VP8, VP9 codecs; frame rate 23–60 FPS; resolution from 360 to 4096 pixels per side; weight «Maximum of 4GB» source, checked 2026-07-28
TwitCasting
Text length. The limits are given separately by kind of entry (our translation): a comment — "1〜140文字", from 1 to 140 characters; the running line of a broadcast (テロップ, the Set Current Live Subtitle method) — "1〜34文字。全角は2文字、半角は1文字でカウントします", from 1 to 34 characters, and… our translation, the original is in Japanese; the count of characters for the running line is kept by the width of the character, not by their number; the help centre help.twitcasting.tv is closed by… source, checked 2026-08-04
Audio. Audio is described only as the track of a broadcast (our translation): "音声のフォーマット: AAC" — the AAC format; there is no separate bit rate for audio, it is set together with video: "ビットレート: Video+Audioで800kbp程度" — about 800 kbp for video and audio together. The… our translation, the original is in Japanese; the bit rate is announced as common for video and audio, the source does not allow it to be split source, checked 2026-08-04
Upload limits. There is no limit on the size of a file, because the documentation does not describe the uploading of files. Limits on the frequency of requests are announced: for most methods "Limit 60 requests / 60 sec", for the method of getting the thumbnail of a… our translation, the original is in Japanese; these are limits on requests to the interface, and not limits on materials source, checked 2026-08-04
Live streaming. The recommended setting for broadcasting over RTMP (our translation): "映像のフォーマット: h.264" — video h.264; "音声のフォーマット: AAC" — audio AAC; "映像サイズ: 640x360" — the frame size 640x360; "フレームレート: 30fps" — 30 frames per second; "ビットレート: Video+Audioで800kbp程度" — about… our translation, the original is in Japanese; the maximum frame size is directly made dependent on the codec; 800 kbp are called a recommendation, and 1 Mbps is the threshold of a forced disconnection source, checked 2026-08-04
Twitch
Text length. A message in chat — "The message is limited to a maximum of 500 characters". An announcement in chat — "Announcements are limited to a maximum of 500 characters; announcements longer than 500 characters are truncated". The title of a scheduled broadcast… the limits are given separately by kind of entry; no limit for the title of the current broadcast (Modify Channel Information) is announced in the API reference source, checked 2026-08-04
Live streaming. The protocol for receiving the signal is RTMP: "Real-Time Messaging Protocol (RTMP)", an address of the form rtmp://<ingest-server>/app/<stream-key>(?bandwidthtest=true). The developer documentation gives no numerical requirements (bit rate, resolution… that very "Broadcasting Guidelines" page (help.twitch.tv/s/article/broadcasting-guidelines) returns only a loading stub without scripts being executed, so the figures for the bit rate and the… source, checked 2026-08-04
Vimeo
Text length. The platform does not publish limits on the length of the title and the description of a video on the pages available. Only the limit on chapters is set by a number: "One Vimeo video has a limit of 80 chapters", "Chapter titles are limited to 50 characters".… the limit is announced only for chapters; https://help.vimeo.com/hc/en-us/articles/28057066916369-How-to-update-your-video-s-title-and-description was also checked — there are no numbers there; the… source, checked 2026-08-04
Images. Requirements are announced only for the cover image of a video: "Supported file types include: JPG, JPEG, GIF, BMP, TIFF, and PNG. While GIF files are supported, animated GIF files are not currently supported", "Custom thumbnails uploaded undergo slight… the platform has no separate publication of an image — only the cover image of a video; the file size of the cover image is not announced; the site vimeo.com itself returns a verification page… source, checked 2026-08-04
Video. The formats: "Vimeo accepts a variety of video file types, though common formats such as MP4 and MOV are preferred. If a format is not supported, an Invalid File error will be displayed", "All videos uploaded to Vimeo will be converted to square pixels". The… almost all the numbers are named as recommended ("we recommend"), the only obligatory thing is the refusal to accept an unsupported format; the file… source, checked 2026-08-04
Video duration. "We also do not support uploads of videos longer than 24 hours" — there is one limit, 24 hours. The platform does not set a lower boundary for duration the limit is a general one and does not depend on the tariff — unlike the limit on the volume of storage; the site vimeo.com itself returns a verification page "Verify to continue... confirm that… source, checked 2026-08-04
Audio. The platform has no independent upload of an audio file — audio exists only as a track of a video, and the track is obligatory: the recommended settings are "Audio codec: AAC-LC (Low Complexity AAC)", "Data rate: 320 kb/s", and moreover "this is higher than… the numbers are named as recommended; the only unconditional action of the platform is the conversion of the sampling rate to 48 kHz; the site vimeo.com itself returns a verification page "Verify to… source, checked 2026-08-04
Upload limits. The limit depends on the tariff and on the date of the creation of the account, and the platform names three different ways of counting. 1) "Total storage (most plans)": "Most plans–Starter, Standard, and Advanced accounts created on or after June 17, 2024… the limit depends on the tariff and on the date of the creation of the account (the boundary is 17 June 2024); the help centre gives no numerical values of the volume by tariff; 200 GB is named as… source, checked 2026-08-04
Live streaming. источники расходятся: The protocol is RTMP and RTMPS. The recommended settings of an external encoder: "Codec: H.264", "Output resolution: 1920 x 1080 (maximum)", "Frame rate: 30fps is recommended (max input is 60fps)", "Key frame interval: 3 seconds". For 4K the limits are… the source contradicts itself: in the guide to the encoder the maximum resolution is named as "1920 x 1080 (maximum)", while a separate article of the same help centre describes broadcasting in 3840… source, checked 2026-08-04
X (Twitter)
Text length. The limit on the length of a post: "Posts on X can contain up to 280 characters". It is not bytes that are counted: the Latin alphabet, punctuation marks and ordinary characters weigh 1, emoji and CJK characters (Chinese, Japanese, Korean) — 2. Links are… subscribers on the paid plans do have longer posts, but this could not be verified against the official help centre: https://help.x.com/en/using-x/how-to-tweet-longer-posts returns 403 even though… source, checked 2026-08-04
Images. "Supported image media types: JPG, PNG, GIF, WEBP", "Image size: <= 5 MB". For a GIF animation the limits are separate: "<= 15 MB", "Resolution: <= 1280x1080 (width x height)", "Number of frames: <= 350", "Number of pixels: <= 300 million (width * height * num_frames)" the limits are given for uploading through the API; a GIF counts as a separate kind of attachment and not as an image source, checked 2026-08-04
Video. The obligatory requirements: "Frame rate: must be 60 FPS or less", "Dimensions: must be between 32x32 and 1280x1024", "File size: must not exceed 512 mb", an aspect ratio "between 1:3 and 3:1", "Pixel aspect ratio: must have 1:1". The recommended ones: "Video… some of the figures are obligatory ("must"), some are recommended — in the source these are different lists source, checked 2026-08-04
Video duration. "Duration: must be between 0.5 seconds and 140 seconds" — that is, from half a second to 140 seconds this is the limit for uploading through the API; announcements about longer clips for the paid subscriptions could not be found on the accessible official pages, the help centre help.x.com returns 403 source, checked 2026-08-04
Upload limits. Per post: "You may attach up to 4 photos, 1 animated GIF or 1 video in a Post". The maximum size by kind of media: an image 5 MB, a GIF 15 MB, a video 512 MB (with media_category=amplify_video). A video is uploaded in parts (chunked upload) the number of attachments and the sizes — https://docs.x.com/x-api/media/quickstart/best-practices ; the procedure for uploading in parts — https://docs.x.com/x-api/media/quickstart/media-upload-chunked source, checked 2026-08-04
Text length. Numbers are announced only for advertising formats (our translation, the original is in German). XING Ads: "Titel: 60 Zeichen", "Beschreibung: 140 Zeichen". XING Lead Ads: "Überschriften: 60 Zeichen", "Beschreibung: 120 Zeichen"; in the form itself "Titel: 60… our translation, the original is in German; all the numbers relate to advertising, and not to ordinary publication; the help centre help.xing.com (and its former address faq.xing.com), where the… source, checked 2026-08-04
Images. The requirements are given separately by advertising format (our translation, the original is in German). XING Ads: "Empfohlenes Bildformat: 16:9 oder 1:1", "Mindestgröße: 1200 x 675 px oder 1080 x 1080 px", "Formate: JPG, PNG", "Maximale Dateigröße: 10 MB"… our translation, the original is in German; the dimensions are given as minimum, and not as exact; the platform does not publish requirements for an image in an ordinary post — the help centre is closed by a Cloudflare check source, checked 2026-08-04
Video. XING Video Ads: AVI, MOV, MP4 up to 5 GB; WebVTT or SRT subtitles up to 10 MB; autoplay without sound by default; 80 characters of text, a 60-character headline The official creative requirements source, checked 2026-07-28
Video. The requirements for advertising video (our translation, the original is in German): "Videoformate: AVI, MOV, MP4", "Dateigröße: Max. 5GB Video", captions — "Max. 10 MB Untertitel" in the formats "WebVTT, SRT". The aspect ratio: "optimal 16:9, andere Formate… our translation, the original is in German; these are the requirements for advertising video; the platform does not write about video in an ordinary post on the accessible pages source, checked 2026-08-04
Upload limits. The size limits are announced by kind of advertising material (our translation, the original is in German): an image — "Maximale Dateigröße: 10 MB" (for Lead Ads the same "Max 10 MB"), video — "Max. 5GB Video", the file of captions — "Max. 10 MB Untertitel".… our translation, the original is in German; the limits for ordinary publications are not published; the developer portal dev.xing.com describes only embeddable buttons, and its /docs section requires… source, checked 2026-08-04
YouTube
Text length. The title of a video — "a character limit of 100 characters"; the description of a video — "a character limit of 5,000 characters"; in both cases they "cannot include invalid characters" the limits are given separately for the title and for the description; there is nothing on this page about the length of the text of a community post source, checked 2026-08-04
Images. A custom video thumbnail: a resolution of 3840 x 2160 pixels with a minimum width of 640 pixels, an aspect ratio of 16:9 ("Try to use a 16:9 aspect ratio"), the formats JPG, GIF or PNG. The maximum file size depends on the device the upload is made from: from… the thumbnail is available after the account has been verified; the size depends not on the plan but on where it is uploaded from source, checked 2026-08-04
Video. The containers accepted: .MOV, .MPEG-1, .MPEG-2, .MPEG4, .MP4, .MPG, .AVI, .WMV, .MPEGPS, .FLV, 3GPP, WebM, DNxHR, ProRes, CineForm, HEVC (H.265). The recommended encoding: an MP4 container with the moov atom at the start of the file (Fast Start), the H.264… the list of containers is taken from https://support.google.com/youtube/troubleshooter/2888402 ; the bit rates are called recommended, not obligatory source, checked 2026-08-04
Video duration. Before the account is verified — videos no longer than 15 minutes ("you can upload videos that are up to 15 minutes long"); after verification — longer. The general ceiling is set together with the size: "The maximum file size you can upload is 256 GB or 12… the limit depends on the verification of the account; on Shorts — https://support.google.com/youtube/answer/10059070 ; the help centre notes that earlier videos may be longer than 12 hours, because… source, checked 2026-08-04
Audio. There is no separate audio format: "audio files, like MP3, WAV, or PCM files, can't be uploaded to create a YouTube video" — the help centre advises first making a video out of the audio. For the audio track of a video AAC-LC or Opus or Eclipsa Audio is… the ban on uploading audio directly — https://support.google.com/youtube/troubleshooter/2888402 source, checked 2026-08-04
Upload limits. File size: "The maximum file size you can upload is 256 GB or 12 hours, whichever is less". The number of uploads per twenty-four hours is limited, but the figure itself is not announced: "Limits may vary by country/region or channel history", "Copyright… the platform deliberately does not publish the daily number of uploads and makes it dependent on the country and on the history of the channel; the file size — https://support.google.com/youtube/answer/71673 source, checked 2026-08-04
Live streaming. The RTMP/RTMPS protocol. The video codecs H.264, H.265 (HEVC), AV1; a frame rate of up to 60 frames per second; a keyframe frequency of 2 seconds is recommended, 4 seconds at most. Audio AAC or MP3 (5.1 only for AAC in RTMP/RTMPS), a bit rate of 128 kbps for… the bit rates are called recommended source, checked 2026-08-04
VKontakte
Text length. The limits are announced separately and not for all kinds of entries. The title of a video — "The maximum number of characters is 128", the description of a video — "The maximum number of characters is 5,000" (the video.save method). An answer option in a… the length of the text of a wall post is not announced in the developer documentation; the poll limits — https://dev.vk.ru/ru/method/wall.post Quoted text is our translation from Russian. source, checked 2026-08-04
Images. A photograph on the wall: "Permitted formats: JPG, PNG, GIF", "The sum of the height and the width is no more than 14,000 pixels", "A file of no more than 50 MB", "An aspect ratio of no less than 1:20". A photograph in an album — the same requirements plus… "the sum of the height and the width" is the sum of the two sides, not each side; the story — https://dev.vk.ru/ru/api/upload/story-in-profile ; the snippets — https://dev.vk.ru/ru/method/wall.post Quoted text is our translation from Russian. source, checked 2026-08-04
Video. A video into a profile: "Permitted formats: AVI, MP4, 3GP, MPEG, MOV, MP3, FLV, WMV". A story video has separate requirements: "Permitted formats: H.264, AAC, MP4", "A maximum resolution of 720×1280 px", "30 fps". The documentation names neither a maximum… the platform's list of video formats also has MP3 in it — the source contradicts itself, because that is an audio format; the requirements for a story — https://dev.vk.ru/ru/api/upload/story-in-profile Quoted text is our translation from Russian. source, checked 2026-08-04
Audio. An audio message is a separate format with its own requirements: "Permitted formats: OGG, OPUS", "A sampling rate of 16 kHz", "A bit rate of 16 kbps", "A duration of no more than 60 minutes" these are the requirements precisely for an audio message in correspondence, not for music source, checked 2026-08-04
Upload limits. Per wall post: "no more than 10 media items (photo, video)", up to 10 audio recordings or one playlist, album or podcast, one poll, one file. Photographs into an album — "No more than 5 photographs per request", each "no more than 50 MB". A story image — "no… the daily limit of 5,000 calls applies to an application, not to a user; the file sizes — the upload pages in https://dev.vk.ru/ru/api/upload/overview Quoted text is our translation from Russian. source, checked 2026-08-04
Live streaming. Live streams exist at the level of the interface: the video.startStreaming method "Obtains an RTMP address for broadcasting video" — that is, the RTMP protocol. The developer documentation names neither a bit rate, nor a resolution, nor codecs only the protocol is named; there are no numerical requirements for a live stream in the documentation Quoted text is our translation from Russian. source, checked 2026-08-04
Dzen
Text length. The limits are given separately by kind of publication. An article: "The maximum length is 140 characters" (the title), "The maximum length of the text is 100,000 characters including spaces", "The maximum length of the description is 2,000 characters". A… the limits for a post — https://dzen.ru/help/ru/channel/post.html , for a video — https://dzen.ru/help/ru/channel/video.html , for a channel — https://dzen.ru/help/ru/channel/channel-management.html Quoted text is our translation from Russian. source, checked 2026-08-04
Images. The channel cover image: "in JPG, BMP or PNG format; no more than 10 MB", for computers "with a resolution of no less than 1500 × 250 pixels; with an aspect ratio of 6:1", for telephones "with a resolution of no less than 960 × 540 pixels; with an aspect… the possibility of uploading a channel cover image depends on the number of subscribers (no fewer than 500); the pictures of publications — https://dzen.ru/help/ru/channel/article.html and https://dzen.ru/help/ru/channel/post.html Quoted text is our translation from Russian. source, checked 2026-08-04
Video. The recommended encoding parameters: "MP4 format", "Place the moov atom at the start of the file (fast start), without edit lists", "The maximum permissible resolution is FullHD", "Size Up to 70 GB", "Frame rate The one the video was shot at, but no higher… the platform calls these parameters recommended, but the size and the resolution are given as maximums; the requirements for Clips — https://dzen.ru/help/ru/mobile/short-video.html , and they can be… source, checked 2026-08-04
Video duration. Video: "The length of a video Up to 480 minutes". Clips: "The minimum length of a clip is 5 seconds, the maximum is 2 minutes", and moreover "If a vertical video in the 9:16 format lasting more than 120 seconds is uploaded, it will be published in the Video… a minimum is announced only for Clips; broadcasts — https://dzen.ru/help/ru/channel/vk-video-live.html Quoted text is our translation from Russian. source, checked 2026-08-04
Audio. The platform has no separate audio format: the requirements for audio are described as part of the video file — "Audio codecs AAC, stereo; Sampling rate: 96 kHz, 48 kHz or 44.1 kHz", "The volume of the audio track Below -12 LUFS". It is separately stipulated… there are requirements for audio, but audio is not an independent format of publication on Dzen Quoted text is our translation from Russian. source, checked 2026-08-04
Upload limits. "From one to twenty videos can be uploaded to Dzen at once". The size of a video file — "Up to 70 GB". A picture in a post — "The maximum size of one picture is 30 MB", in one post "no more than 10 of them". A picture in an article — "up to 30 MB". The… the number of files at a time is announced only for video (from 1 to 20) Quoted text is our translation from Russian. source, checked 2026-08-04
Live streaming. Broadcasts go through VK Video: only two numerical requirements are announced — "The size of the resulting video must not exceed 70 GB" and "A broadcast must not be longer than 8 hours". When it ends "its recording will automatically appear in the channel in… there are no numerical requirements for the signal itself (bit rate, resolution, protocol) on the page Quoted text is our translation from Russian. source, checked 2026-08-04
Odnoklassniki
Video. The documentation names neither formats, nor codecs, nor resolution. Only the file size is announced: "Files of a size from 16 KB to 1 GB are supported" the limit is set on both sides — there is both a minimum (16 KB) and a maximum (1 GB) Quoted text is our translation from Russian. source, checked 2026-08-04
Video duration. The duration is limited only for attachments shot on the spot: "VIDEO – a video attachment from the camera (a limit of 3 minutes in length)", "AUDIO_RECORDING – an audio recording from the microphone (a limit of 3 minutes in length)". For video from disk… the limit depends on the kind of attachment: what is shot from the camera — 3 minutes, what is uploaded from disk — with no announced limit Quoted text is our translation from Russian. source, checked 2026-08-04
Audio. Audio is described as a kind of attachment and not as a format: "AUDIO_RECORDING – an audio recording from the microphone (a limit of 3 minutes in length)". The documentation names neither a codec, nor a sampling rate, nor a bit rate only the duration of a recording from the microphone is announced Quoted text is our translation from Russian. source, checked 2026-08-04
Upload limits. The file size: "Files of a size from 16 KB to 1 GB are supported". The number of photographs at one time is set by the count parameter ("The number of photographs to add. The default value: 1"), but the documentation gives no maximum value. A general… the limit on the number of files at a time is not published; on the frequency of calls — https://apiok.ru/dev/limits Quoted text is our translation from Russian. source, checked 2026-08-04
ニコニコ動画 (Niconico)
Upload limits. upload limits: file up to 6 GB, resolution up to 4096x2160 horizontally and up to 2160x4096 vertically, frame rate up to 60, audio sample rate up to 192 kHz, up to 5.1 (6) audio channels (2 on delivery), duration up to 6 hours The specification page was updated on 15 April 2026 source, checked 2026-07-28
微信 (WeChat)
Text length. источники расходятся: For an article in a draft (our translation): the title — "总长度不超过32个字" (no more than 32 characters); the author — "总长度不超过16个字" (no more than 16 characters); the summary — "总长度不超过120个字", and if the field is not filled in, "默认抓取正文前54个字" (the first 54 characters… our translation; the original is in Chinese; the source contradicts itself: about the main text it says at once "no more than 2 kb", "fewer than 20,000 characters" and "smaller than 1 M" source, checked 2026-08-04
Images. источники расходятся: A permanent material (our translation): "图片（image）: 10M，支持bmp/png/jpeg/jpg/gif格式" — an image of up to 10 M, the formats bmp, png, jpeg, jpg, gif; "缩略图（thumb）：64KB，支持JPG格式" — a thumbnail of up to 64 KB in JPG. An image inside an article is uploaded by a… our translation; the original is in Chinese; on the page for temporary materials the same platform writes in one place "文件大小限制：图片2MB/视频10MB" (an image 2 MB), and a line below "图片（image）: 10M"… source, checked 2026-08-04
Video. The only requirement for video (our translation): "视频（video）：10MB，支持MP4格式" — a video file of up to 10 MB, the MP4 format. The documentation names neither a codec, nor a resolution, nor an aspect ratio, nor a bit rate our translation; the original is in Chinese; the same figure is repeated on the page for temporary materials source, checked 2026-08-04
Audio. Audio is a separate kind of material (our translation): "语音（voice）：2M，播放长度不超过60s，mp3/wma/wav/amr格式" — up to 2 M, playback no longer than 60 seconds, the formats mp3, wma, wav, amr. Separately there is high-quality audio obtained through the JSSDK… our translation; the original is in Chinese; on the page for temporary materials the list of formats is shorter — "支持AMR\MP3格式", that is, only amr and mp3 source, checked 2026-08-04
Upload limits. The limits of the material store (our translation): "公众号的素材库保存总数量有上限：图文消息素材、图片素材上限为100000，其他类型为1000" — articles and images up to 100,000 items, other kinds up to 1,000. A temporary material lives for three days: "媒体文件在微信后台保存时间为3天，即3天后media_id失效". Images… our translation; the original is in Chinese; a limit on the number of files per request is not announced — what is announced is the limit of the store source, checked 2026-08-04
抖音 (Douyin)
Video duration. the video duration may not exceed 15 minutes — this is recorded in the error table as code 2114006; a file larger than 300 MB gives code 2190005, "file too large" The limit is published not in the text of the rules but in the description of the error codes source, checked 2026-07-28
네이버 밴드 (Naver Band)
Text length. The only announced limit on the length of text relates to a poll inside a post: "Poll: You can attach 10 polls per post, up to 50 options per poll, and up to 200 characters for the title and option titles" — up to 200 characters for the title of the poll and… the number 200 is announced only for a poll; for a post and a comment there is no number either in the article about attachments or in the article about chats https://help.band.us/help/1028 source, checked 2026-08-04
Images. The help centre names no formats, resolution or size of a single photo — only the quantities and the way to control the size are named: "Photo: Up to 100 photos per post, and 5 photos per comment can be attached (the attached image size can be altered in the… the limit on the size of a photo depends on the group's setting, the platform publishes no single figure; the chat limits — https://help.band.us/help/1028 source, checked 2026-08-04
Video. The help centre names neither formats, nor codecs, nor a resolution — only a size and a number. In a post: "Video: Up to 10 videos can be attached per post, up to 3GB and 60 minutes each". In a chat: "Videos – 1 video (must be under 1GB)". In a quiz question… the limits are different for a post, a chat and a quiz; the platform does not publish codecs and a resolution; the chat — https://help.band.us/help/1028 source, checked 2026-08-04
Video duration. The limits are given separately by kind of attachment: video in a post — "up to 3GB and 60 minutes each", that is, no longer than 60 minutes; video in a quiz question — "A video file shorter than 30 minutes"; a voice memo — "Voice Memo: You can attach 10… the live stream — https://help.band.us/help/1256 and https://help.band.us/help/1222 ("You can live stream for up to 2 hours. However, after finishing live streaming, you can start another live stream… source, checked 2026-08-04
Audio. Audio is an independent kind of attachment, but the help centre sets no requirements for the file (a format, a codec, a bit rate), only a quantity and a duration: "Voice Memo: You can attach 10 voice memos per post, up to 30 minutes each". For audio inside a… there are numbers, but the platform does not name a format and a codec source, checked 2026-08-04
Upload limits. The limits per one post are listed one by one: "Photo: Up to 100 photos per post, and 5 photos per comment"; "Video: Up to 10 videos can be attached per post, up to 3GB and 60 minutes each"; "File: Up to 5 files can be attached per post, no more than 1GB… the storage period depends on the duration of the video and on the volume purchased — https://help.band.us/help/1077 ; the chat limits — https://help.band.us/help/1028 source, checked 2026-08-04
Live streaming. The help centre does not publish numerical requirements for the signal (a bit rate, a resolution, a codec, a protocol). Only the conditions are announced: the duration "up to 2 hours per session", the number of live streams is not limited, "only one live… the possibility of running a live stream depends on the rights granted by the owner of the group; the requirement of 2 GB — https://help.band.us/help/1226 ; about the encoder… source, checked 2026-08-04
카카오톡 (KakaoTalk)
Text length. The limits are given by kind of message template (our translation). A text template: "텍스트 정보, 최대 200자" — up to 200 characters. A list template: "리스트 상단에 노출되는 메인 타이틀, 최대 200자" — the title up to 200 characters. In the product block: "이미지 아이템의 제목 최대 2줄, 최대 24자까지… our translation; the original is in Korean; the limits are described as "how much is displayed on the screen", not as a prohibition on sending source, checked 2026-08-04
Images. The image is passed by a link and must be uploaded to the platform's server beforehand (our translation): "업로드 가능한 이미지 파일 크기: 5MB 이하" — a file of up to 5 MB; "이미지 보관 기간: 카카오 서버에 최대 100일간 보관, 이후 자동 삭제" — it is stored for up to 100 days. The link must conform… our translation; the original is in Korean; the maximum size is announced for uploading through the software development kit; the sizes of a position — https://developers.kakao.com/docs/latest/ko/message-template/default source, checked 2026-08-04
Upload limits. The image: "업로드 가능한 이미지 파일 크기: 5MB 이하". In the list template the content is "2개 이상 필수, 최대 3개" — from two to three positions; buttons "버튼 목록, 최대 2개" — no more than two our translation; the original is in Korean; the numbers of positions and of buttons — https://developers.kakao.com/docs/latest/ko/message-template/default source, checked 2026-08-04
How to use this
- Check the limit before you shoot, not after. Reshooting is cheaper than re-editing to someone else's format.
- See what the limit depends on. YouTube's «15 minutes» applies before the account is verified; after verification the limit is different. Such caveats are kept here rather than collapsed into a single number.
- A contradiction in the source is not our mistake. Where a platform gives two different limits on one page, both are shown: «источники расходятся». Plan by the stricter figure.
- Mind the check date. Requirements change quietly, and platforms make no announcement of it.
On method. Only the platforms' own documentation: help centre, pages for creators, API documentation. Third-party summary tables of sizes are not taken into the catalogue: there is no way to check them, незаметно.
See also: platform restrictions · making content with AI · what platforms require of AI content