Free tool
Thread Splitter for X and Threads
Paste something too long for one post and get it back as a numbered thread that breaks on sentence boundaries, sized for the 280 characters X allows or the 500 on Threads.
Last updated: 2026-08-03
Splitting a long draft by hand is the kind of task that looks like it takes two minutes and takes twenty. You count to 280, you land mid-clause, you move the break, and now every number in the thread is wrong because you added a post in the middle.
This splitter does the arithmetic instead. It reads your text as paragraphs and sentences rather than as a character stream, packs as many whole sentences into each post as will fit, and only ever cuts inside a sentence when a single sentence is genuinely longer than the limit. Numbering is applied last and charged against the same budget as the words, which is the part most manual splits get wrong.
Everything runs in your browser. There is no account, no upload, and no copy of your draft on our side: the text you paste stays in the page you are reading.
0 characters0 posts280 per post on X (Twitter)
Links are weighted at 23 characters each, the way X charges them.
The prefix spends characters like any other text, so it is reserved before the split. A single post is never numbered.
Your thread for X (Twitter)
Paste your draft above and it appears here as numbered posts, each one packed with whole sentences and measured against the 280 characters X (Twitter) allows. Nothing is uploaded and nothing is stored.
Breaks land on sentence boundaries, and paragraph breaks in your draft are preferred over sentence ones.
Limits on X and Threads
Both networks cap a single post and expect anything longer to become a chain. The difference is what a character costs: X rewrites links and charges a flat rate for them, Threads charges every character of the URL as written.
| Network | Tier | Limit per post | What that means in a chain |
|---|---|---|---|
| X (Twitter) | Standard account | 280 chars | Every link counts as 23 characters no matter its length |
| X (Twitter) | Premium account | 25,000 chars | A standard post never folds. Premium posts longer than 280 characters collapse behind a "Show more" toggle in the timeline. |
| Threads | Every account | 500 chars | Each post in a chain gets its own 500 characters, so longer thoughts are split across replies rather than stretched. |
Limits verified 2026-07-31. Threads has no classic hashtag block: a post carries a single topic tag, and its text is charged against the same 500 characters.
Thread numbering conventions
Numbering is a reading cue, not a formality: it tells someone how much is left before they decide whether to start. It is also plain text, so whichever style you pick is charged against the same limit as your sentences.
1/5 style
The default. Readers can see how much is left before they commit, and anyone landing on post 4 knows there are three above it.
1/ style
For threads you might extend later. Nothing promises a length, so adding a post the next morning does not make every earlier number wrong.
No numbering
When each post has to stand alone, for example if you expect individual posts to be reshared out of context. You lose the reading cue.
The cost is small but it is paid on every post. On X a "12/14 " prefix takes 6 characters off all 14 posts, which is 84 characters of thread gone. The splitter works that reserve out before it packs, and it drops numbering entirely when your text fits in one post.
Writing a thread that gets finished
- Write the first post last. It is the only one most people see in the feed, so it has to work as a standalone statement rather than as the opening half of a sentence.
- Leave a blank line between paragraphs before you paste. The splitter treats a paragraph break as a strong hint and will start a new post there whenever the next sentence does not fit.
- Keep threads short enough to finish. Five to ten posts is where most threads hold attention; past fifteen the completion rate falls off sharply and the last posts are read by almost nobody.
- Numbering is not free. On X a "12/14 " prefix costs six of your 280 characters on every single post, so switch to "1/ " or turn numbering off if the thread is running tight.
- Put the link in the last post, not the first. A URL costs 23 characters on X wherever it sits, and a link in post one gives people somewhere to go before they have read anything.
- Read the split before you publish. The tool breaks on sentences, but only you know which sentence is the punchline that deserves a post of its own.
Frequently asked questions
Does the numbering count against the character limit?
Yes. A prefix like "3/12 " is ordinary text as far as X and Threads are concerned, so it spends characters like anything else. This splitter reserves room for the widest prefix in the thread before it packs, then repacks if adding the numbers changed how many posts you need.
How are links counted on X?
Every URL is rewritten through t.co and charged at a flat 23 characters, however long the original link is. The splitter applies that weighting when you pick X, so a post with a 180 character tracking URL is measured the way X will measure it, not the way your text editor does.
Is my text uploaded or stored anywhere?
No. The splitting happens in your browser with JavaScript, nothing is sent to a server, and nothing is saved. Close the tab and the draft is gone.
How many posts should a thread be?
Five to ten for most topics. That is long enough to develop an idea and short enough that people reach the end. If your draft splits into twenty-five posts, the honest fix is usually to publish it as an article and use a short thread to sell the click.
Where does the splitter break the text?
At sentence boundaries first, and at paragraph boundaries in preference to sentence ones. A sentence is only cut open when it is longer than a whole post on its own, and then it breaks on a space rather than mid-word. Emoji and flags are never split down the middle.
Can I use the same draft for X and Threads?
You can, but switch the network toggle and check both. Threads gives you 500 characters per post against 280 on X, so the same text usually becomes roughly half as many posts, and the breaks land in different places.
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