Free tool
Social media character counter
Type or paste, and see how the same text lands on every network at once — how many characters it is, how many each one allows, and how far over or under you are.
- Characters
- 0
- Words
- 0
- Lines
- 0
| Network | Limit | Remaining |
|---|---|---|
| X | 280 | 280 |
| Bluesky | 300 | 300 |
| Threads | 500 | 500 |
| 2,200 | 2,200 | |
| 63,206 | 63,206 | |
| 3,000 | 3,000 | |
| Mastodon | 500 | 500 |
How this works
- The limits are the product’s own. They are read from the same capability table postfast’s composer warns from, so a limit that changes in the product changes here in the same commit.
- A count near a limit is an estimate. X counts a URL as a fixed-width t.co link and weights CJK characters double; Bluesky counts graphemes rather than code units. Neither weighting is modelled, so treat anything within a few characters of a limit as uncertain in both directions.
- Mastodon’s 500 is a default, not a rule. Each Mastodon instance sets its own limit and plenty run 1,000 or more. 500 is what Mastodon ships with and the only number a static table can honestly claim.
- postfast's own ceiling is 5,000 characters. That applies whatever a post is aimed at, and it is why Facebook’s 63,206 is a description of Facebook rather than something you can reach through postfast.
- It runs here, in your browser. Nothing is sent anywhere, stored, or logged.
Common questions
- What is the character limit on X?
- 280 for a standard post. postfast counts against 280 and warns rather than blocks near the boundary, because X weights links and CJK characters in ways a plain count does not model.
- Why do different networks count the same text differently?
- Because they measure different things. X substitutes a fixed width for every URL and counts CJK characters double; Bluesky counts graphemes, so an emoji built from several code points counts as one.
- Does this count hashtags and mentions separately?
- No — on every network postfast publishes to, hashtags and mentions count as ordinary characters.
The other free tools
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This is one check out of a product full of them
postfast runs this inside its composer, on every post, against every network you publish to. Join the waitlist for early access.