Platform limitations
What each platform's API really allows
Every social network sets hard rules for tools that post on your behalf: caption lengths, file specs, daily quotas, and what analytics and messages they share. No scheduler can work around them - so we document them instead. These pages reflect the exact limits Posty enforces, verified against each platform's official developer documentation.
Instagram limitations
Instagram's caption, hashtag, image, Reel and Story limits when posting via the API.
Facebook limitations
Facebook Page caption, photo, video and Reel limits when publishing via the API.
Threads limitations
Threads' 500-character limit, carousel and video specs, link caps and publishing quotas via the API.
TikTok limitations
TikTok's video size, length, resolution and daily posting limits via the Content Posting API.
YouTube limitations
YouTube's title, description, file size and duration limits via the Data API, how Shorts are detected, and what analytics scheduling tools can read..
LinkedIn limitations
LinkedIn's 3,000-character commentary limit, image and video specs via the API, and the analytics available to scheduling tools like Posty..
Pinterest limitations
Pinterest's title, description and image limits when creating pins via the API, plus the analytics and audience data available to scheduling tools..
Bluesky limitations
Bluesky's 300-character limit, image and video specs on the AT Protocol, and why no scheduling tool can show you view counts..
Discord limitations
Discord's message length and file size limits when posting via webhooks, and why analytics and inbound messages aren't available..
Why do these limits exist?
Platforms apply the same rules to every third-party tool through their official APIs - they protect users from spam and keep feeds healthy. If a tool claims it can exceed them, it's either breaking the platform's terms or it isn't using the official API. Posty validates your post against these limits while you compose, so anything you schedule is something the platform will actually accept.