Platform limits and restrictions
Two different things constrain a post. Postbean’s own upload caps are validated before anything is sent; everything else is the network’s own rule, applied at publish time.
Postbean’s limits
Section titled “Postbean’s limits”| Limit | |
|---|---|
| Image | 8 MB · JPG, PNG, WebP |
| Video | 100 MB · MP4, MOV |
| Media per post | 35 items |
| Caption | 5,000 characters |
| Subtitles | 512 KB · SRT, VTT |
| Scheduled posts | Unlimited, any date in the future |
The 5,000-character caption is Postbean’s field length. What actually publishes is capped by each network below, and the composer’s counter shows that network’s number while you type.
Caption length by network
Section titled “Caption length by network”| Network | Maximum | Recommended |
|---|---|---|
| X (Twitter) | 280 | 260 |
| Bluesky | 300 | 280 |
| Threads | 500 | 450 |
| 500 | 200 | |
| 2,200 | 1,200 | |
| TikTok | 2,200 | 150 |
| 3,000 | 1,300 | |
| YouTube | 5,000 | 800 |
| No practical limit | 500 | |
| DEV Community | No practical limit | — |
The recommended figure is where the network starts truncating in the feed, not a hard rule.
What each network accepts
Section titled “What each network accepts”| Network | Images | Video | Title field | First comment |
|---|---|---|---|---|
| Yes · carousel to 10 | Yes | — | Yes | |
| Yes · multi-photo | Yes | — | Pending a Meta permission | |
| Threads | Yes · carousel to 20 | Yes | — | Yes |
| X (Twitter) | Yes | Yes | — | — |
| TikTok | — | Yes | — | — |
| YouTube | — | Yes | Yes | Yes |
| Yes · multi-image | Yes | — | Not available to our app | |
| First image only | Yes | Yes | — | |
| Bluesky | First image only | Yes | — | Yes |
| DEV Community | Cover image | — | Yes | — |
Posting quotas
Section titled “Posting quotas”These come from the networks and are not something Postbean can raise:
| Network | Quota |
|---|---|
| 25 posts/day per account | |
| Threads | 250 posts/day per account |
| Facebook Pages | Pages only — no personal profiles or groups |
| TikTok | Daily video cap and maximum duration read from your own account |
| YouTube | Roughly 6 uploads/day on the free quota · custom thumbnails need a verified channel |
| 500 API calls/day per token · personal profiles only | |
| Bluesky | ~5,000 writes/hour · video needs a verified email |
| Every pin needs a board — the post’s own, or the account’s default |
Not supported yet
Section titled “Not supported yet”- Google Business appears in previews but cannot be connected yet.
- LinkedIn Company Pages — needs LinkedIn’s Community Management API.
- Multi-post threads on X and Threads.
- Instagram trial reels and TikTok photo posts — neither is exposed by the platform’s API.