Social Media Character Counter (X, Threads, Instagram, YouTube, Bluesky and more)

Count a post the way X (CJK characters 2, URLs 23), Threads, Instagram, YouTube title and description (bytes), Bluesky, Mastodon and LINE document it, and see what is left and where the text goes over.

  • Runs in your browser with cited reference data

Your text is counted on this page only and is not sent anywhere.

The default is 500 characters; some servers use a different limit.

Calculated with the limits and counting rules in each service’s official documentation (checked 2026-11-06). Values whose counting method is not published are marked "Reference". Rules can change, and this does not guarantee that a post will go through.

Result

Over the limit on 1 of 8.

How to use

  1. Type or paste your post (a sample text is filled in to start).
  2. For each service you see the count in its own unit, the limit and what is left or over. When the text is too long, the point where it goes over is shown.
  3. Change the Mastodon limit to match your server. "Reference" marks services that do not publish how characters are counted.

FAQ

How many Japanese or Chinese characters fit in an X post?

X uses weighted counting: Chinese, Japanese and Korean characters count 2 each, so text in those scripts alone fits 140 characters. Every URL counts 23 whatever its length.

Why is my YouTube description too long when it has fewer than 5,000 characters?

The YouTube Data API limit is 5,000 bytes in UTF-8. Most Chinese and Japanese characters take 3 bytes, and Vietnamese letters with diacritics usually take 2 or 3 bytes.

What does "Reference" mean?

The service publishes a limit but not what counts as one character. The value shown is an estimate counted in code points or a similar unit.

Notes & limitations

  • What you enter is processed only on this page and is not sent to YUCTS servers.
  • Calculated from each service’s official documentation (checked 2026-11-06); it does not guarantee that a post will go through. Rules can change without notice.
  • Facebook is not included because no official character limit could be confirmed. The LINE limit is for text messages sent through the Messaging API, not for personal chats.
  • X is counted with the standard 280 limit, and URLs that do not start with http(s):// or www. (such as example.com) count as plain text.
  • Emoji and combined characters are split with the browser’s Intl.Segmenter; older browsers without it use a simplified method.

Data sources