Every X (Twitter) limit, explained
Precise answers to the limit questions, with the weighted-counting rules spelled out and a live counter on each page. Facts are stamped with the date we last verified them.
The character limit on X (Twitter) is 280 weighted characters per post for free accounts. Counting is weighted, not literal: every link counts as exactly 23 characters regardless of its length, and most emoji and CJK (Chinese, Japanese, Korean) characters count as 2 each. X Premium subscribers can publish posts up to 25,000 characters, but only roughly the first 280 show in the timeline before the 'Show more' fold.
X Premium subscribers can publish posts up to 25,000 characters, versus 280 weighted characters on free accounts. Long posts display collapsed in the timeline: roughly the first 280 characters show, followed by a 'Show more' link that expands the full text. Premium also unlocks bold and italic text formatting inside posts.
X does not document a maximum number of posts in a thread. The composer lets you chain a long run of posts before publishing — third-party clients report around 50 per batch — and there is no hard cap on a thread's total length either way, because you can always extend it by replying to your own last post. Each post in the thread keeps its own limit: 280 weighted characters on free accounts, up to 25,000 with Premium.
The X (Twitter) bio is limited to 160 characters — this is the one X states outright in its own help docs. The display name is capped at 50 characters per X's API documentation, the location field is a short free-text field, and the website field takes one URL.
The free character counter runs the official twitter-text parser in your browser: links at 23, emoji at 2, exactly as X counts.