Networks & rules
Publish to selected accounts with one request. Each network has its own caption, media and placement rules. These are the same requirements Mellow checks before sending.
Ten social networks, eleven integration modes: TikTok and TikTok Business connect to the same network.
A professional (Business or Creator) Instagram account. A personal account cannot publish through any API.
A personal or creator TikTok account.
A TikTok Business account. Use it when you need business analytics; otherwise the ordinary TikTok connection is simpler.
A Google account with a YouTube channel. Uploads count against the channel's daily API quota.
Hub posts through its provider's X app, so you need no X developer account or API credits of your own.
Posts as your personal profile, or as a company page you administer.
The Threads account attached to your Instagram login.
Hub connects Bluesky with your handle and an app password rather than a sign-in screen, so an agent cannot complete this step alone.
A Pinterest business account with at least one board to pin to.
A Facebook Page you administer. Personal timelines cannot be published to through the API.
A Telegram channel you administer. You add Mellow's bot to it with one right, to post messages; Mellow never sees your Telegram account.
These are the networks’ own published figures for posting through an API, which is how every scheduler posts. When a network refuses a post for its limit, Mellow Hub does this by itself: waits for the network’s limit to start over and sends it then, up to three times. The post shows until when it waits.
Instagram takes 100 API-published posts from an account within a 24-hour moving period; a carousel counts as one.
Meta for Developers: Instagram Platform, Content Publishing, read 13 October 2026.
TikTok limits the posts made to a creator account through its API in a 24-hour window. The limit varies among creators, typically around 15 a day, and is shared across every app that posts for the account.
TikTok for Developers: Content Sharing Guidelines, read 13 October 2026.
TikTok limits the posts made to a creator account through its API in a 24-hour window. The limit varies among creators, typically around 15 a day, and is shared across every app that posts for the account.
TikTok for Developers: Content Sharing Guidelines, read 13 October 2026.
YouTube gives an API project 100 video uploads a day by default, shared by everybody who uploads through that project; the day starts over at midnight Pacific Time.
YouTube Data API: Quota calculator, read 13 October 2026.
X gives an unverified account 50 original posts and 200 replies a day, split into half-hour limits.
X Help Center: About X limits, read 13 October 2026.
LinkedIn does not publish its limits: its documentation says so, and that they are counted over 24 hours for an app and for each member, and start over at midnight UTC.
LinkedIn API documentation on Microsoft Learn: Rate limiting, read 13 October 2026.
Threads takes 250 API-published posts from a profile within a 24-hour moving period, a carousel counting as one, and 1,000 replies.
Meta for Developers: Threads API overview, rate limiting, read 13 October 2026.
Bluesky counts points for an account: 5,000 an hour and 35,000 a day, three for each record created, which is at most 1,666 records an hour and 11,666 a day.
Bluesky documentation: Rate limits, read 13 October 2026.
Pinterest publishes no number of Pins a day. For an app with Standard access it takes 100 requests a minute from a user for creating, editing or deleting boards and Pins.
Pinterest Developers: Rate limits, read 13 October 2026.
Facebook’s Reels API takes 30 API-published reels within a 24-hour moving period. That page gives no figure for a Page’s other posts.
Meta for Developers: Reels Publishing API, read 13 October 2026.
Telegram publishes no number of posts a day for a channel. It asks a bot to send no more than one message a second in one chat, and answers with an error to a bot that keeps going past that.
Telegram Bots FAQ: My bot is hitting limits, read 13 October 2026.
Mellow Hub reads a video’s length, frame and weight before sending and says so when one is outside these limits; it does not refuse the post, because the network’s API has the last word on a file. To hold one file against all of them, use the free video checker.
3 seconds to 15 minutes · up to 300 MB · 0.01:1 to 10:1 · up to 1920 pixels wide · MP4 or MOV.
Meta for Developers: Instagram Graph API, IG User media (reel specifications), read 7 October 2026.
up to 3 minutes, or 10 minutes for some accounts · up to 4 GB · 360 to 4096 pixels each way · MP4, WebM or MOV. Every creator can post 3 minutes through TikTok’s API; some can post 5 or 10 minutes.
TikTok for Developers: Content Posting API, media transfer guide, read 7 October 2026.
length not published · up to 256 GB.
YouTube Data API: Videos: insert, read 7 October 2026.
0.5 seconds to 20 minutes, or 125 minutes for some accounts · up to 8 GB, or 16 GB for some accounts · 1:3 to 3:1. Without Premium, X’s API takes 20 minutes; with Premium, 125 minutes. A scheduler cannot see which an account has.
X Developer Platform: media upload best practices, read 7 October 2026.
3 seconds to 30 minutes · up to 500 MB · at least 75 KB · MP4.
LinkedIn API documentation on Microsoft Learn: Videos API, read 7 October 2026.
up to 5 minutes · up to 1 GB · 0.01:1 to 10:1 · up to 1920 pixels wide · MOV or MP4.
Meta for Developers: Threads API overview, media specifications, read 7 October 2026.
length not published · size not published.
Bluesky documentation: Uploading video, read 7 October 2026.
4 seconds to 5 minutes · size not published · MP4, MOV or M4V.
Pinterest Help: Review Pin specs; Pinterest Developers: Create boards and Pins (video Pins), read 7 October 2026.
3 to 90 seconds · size not published · at least 540 × 960.
Meta for Developers: Reels Publishing API, video specifications, read 7 October 2026.
length not published · up to 50 MB · MP4; another format may arrive as a file.
Telegram Bot API: sendVideo, read 13 October 2026.
list_platforms or the resource mellow://guide/platforms. It can check requirements before creating a post.