The current limit
The standard post limit on X (formerly Twitter) remains 280 characters for most accounts, a limit that's been in place since 2017 when it doubled from the platform's original 140-character cap. Every paid subscription tier — Basic, Premium, and Premium+ — now shares the same long-form post limit: up to 25,000 characters, roughly 4,000–4,500 words depending on average word length. That's a big jump from an earlier, lower Premium-only limit X used before unifying the tiers, so figures you find elsewhere citing a smaller Premium number (4,000 characters is a common one still floating around) are describing that earlier policy, not the current one.
What actually counts toward the limit
Every visible character counts, including spaces, punctuation, hashtags, and @mentions — there's no special exemption for these the way some people assume. Links are the one notable exception: any URL, regardless of its actual length, is counted as a fixed number of characters (23, as of the platform's long-standing t.co link-shortening behavior) once it's auto-shortened, which is why pasting a very long URL doesn't blow past the limit the way typing out 150 characters of plain text would.
Why your character count might not match what you expect
Certain characters — particularly emoji and some non-Latin scripts — can count as more than one character toward the limit, depending on how they're encoded, which is a common source of confusion when a post that looks short still hits the limit unexpectedly. If you're consistently running into the limit with what looks like a short post, emoji or special characters are a likely culprit worth checking for.
Check your post length
Quick ways to trim a post that's running long
Swapping full words for common abbreviations ("with" → "w/", "and" → "&") is the fastest, most reversible trim. Cutting filler words and redundant qualifiers ("very," "really," "just") usually saves more characters than expected without changing the meaning. If a post is still over, consider whether it genuinely needs to be one post — splitting a longer thought into a short thread is often more effective anyway, since a single dense 280-character post can be harder to read than two clear, shorter ones.