The character limit for a Bluesky post is 300 characters.
Bluesky, the decentralized social network built on the AT Protocol, uses a 300-character limit that sits between X’s 280 and Threads’ 500. The limit encourages short, focused posts while giving you slightly more room than X.
Character limits on Bluesky
| Content type | Limit |
|---|---|
| Post | 300 characters |
| Reply | 300 characters |
| Alt text | 2,000 characters |
| Display name | 64 characters |
| Bio | 256 characters |
| Images per post | Up to 4 |
How Bluesky compares to similar platforms
| Platform | Character limit |
|---|---|
| X (Twitter) | 280 |
| Bluesky | 300 |
| Threads | 500 |
| Mastodon | 500 |
The 20-character advantage over X is subtle but occasionally useful — enough for an extra word or two.
Tips for Bluesky posts
- Be concise — 300 characters rewards clarity and brevity
- Use alt text — Bluesky’s community values accessibility, and alt text has a generous 2,000-character limit
- Custom feeds — Bluesky’s algorithm-free custom feeds mean discoverability works differently than algorithmic platforms
- Link posts — links include rich previews and do count toward the character limit
- Thread for longer content — break longer ideas into connected posts
Character limit in BulkPublish
BulkPublish enforces the 300-character limit for Bluesky posts. When composing Bluesky threads, each part is individually tracked at 300 characters.