X (formerly Twitter) posts are limited to 280 characters. However, CJK (Chinese, Japanese, Korean) characters count as 2 characters each, effectively limiting Japanese posts to 140 characters.

This limit was expanded from 140 to 280 characters in 2017 to allow English-speaking users to convey more information. For CJK languages, the effective limit remained unchanged. X marketing strategy books teach effective post writing.

URLs count as 23 characters regardless of actual length (t.co shortened URLs). Image and video attachments do not count toward the limit. Mentions (@username) are included in the character count.

X Premium subscribers can post up to 25,000 characters, but only the first few lines appear in the timeline, making the opening text especially important. Social media writing guides cover effective expression within character limits.