Instagram limitations
Instagram's API only publishes for professional (Business or Creator) accounts, and applies hard limits on captions, media specs and daily volume. Here is exactly what applies when you schedule through Posty.
Publishing limits
The limits Instagram applies to posts published through its official API. Posty checks every one of these while you compose.
| Limit | Value |
|---|---|
| Caption length | 2,200 characters |
| Hashtags | 30 per caption |
| @ mentions | 20 per caption |
| Carousel size | 2–10 items |
| Image format & size | JPEG, up to 8.0 MB Other formats may be converted or rejected by Instagram. |
| Image aspect ratio | 4:5 to 1.91:1 (feed and carousels) Stories and Reels accept nearly any ratio; 9:16 is recommended. |
| Reels | up to 300.0 MB, 3s to 15 minutes |
| Story video | up to 100.0 MB, 3–60s |
| API publishing volume | 100 posts per rolling 24 hours A carousel counts as one post. Shared across every tool connected to the account. |
Rows marked Posty are current Posty product choices rather than hard platform rules.
Analytics
Views, reach, likes, comments, shares and saves per post, plus account-level reach, profile taps and follower demographics.
- Instagram reports insights with up to 48 hours of delay.
- Follower demographics require at least 100 followers.
- Insights only exist for content posted after the account became a professional account.
Inbox & messaging
Comments and DMs are supported for Business and Creator accounts.
- DM replies are limited to a 24-hour window after the customer's last message - a rule Instagram applies to every tool.
- Message requests from non-followers can only be accepted in the Instagram app.
Good to know
- Personal accounts cannot publish via the API at all - Instagram requires a professional account.
- Instagram has no native scheduling for API posts; Posty's scheduler holds the post and publishes it at the right moment.
- Stories disappear after 24 hours, and their insights expire with them.
These limits apply to every tool
They come from Instagram's official API, so no scheduler can exceed them. Posty validates against every limit on this page while you compose - if your post passes, Instagram will accept it.
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