What the X (Twitter) thread splitter does
A thread is one long idea chopped into several linked posts. The snag is that X (formerly Twitter) caps each post at a fixed number of characters, and counting by hand where one tweet ends and the next begins is tedious — you almost always end up slicing a word in two. This splitter takes your full text and shares it out into tweets that respect the limit without breaking a single word, optionally numbered 1/n, 2/n, and so on.
It runs entirely in your browser: paste the text, pick the limit, and each tweet appears instantly in its own card with a live character count, ready to copy one by one or as the whole thread at once.
How to use it
- Type or paste your long text into the box.
- Set the characters per tweet: 280 for a free X account, 500 for Threads or X Premium. You can enter any value from 10 to 5000.
- Choose the numbering: none, at the start (
1/n text) or at the end (text 1/n). - Copy each tweet with its button, or hit Copy the whole thread to grab every tweet separated by a blank line.
The method: greedy word packing
The algorithm is greedy, word by word. It walks through the words and keeps stuffing them into the current tweet while they fit; the moment the next word would push past the limit, it seals that tweet and starts a new one. That guarantees no word is ever split. The only exception is a single “word” that is longer than the whole limit on its own — say a giant URL or aaaa… of 650 letters — which does get chopped, because there is no other way to make it fit.
Numbering adds a twist most tools ignore: the characters in 1/n also count, and n itself (the total number of tweets) depends on how much text fits, which in turn depends on how much room 1/n steals. The splitter breaks that loop by reserving space for the longest possible label (n/n plus a space) and re-running the split until the tweet count stops changing. The upshot: no fragment, once numbered, ever exceeds the limit.
| Network / plan | Characters per post |
|---|---|
| X (free account) | 280 |
| X Premium (long post) | 25,000 |
| Threads | 500 |
| Bluesky | 300 |
| Mastodon (default instance) | 500 |
Worked example
Take this 154-character text:
A thread is just one idea broken into bite-sized posts. Write the whole thing first, then let the tool cut it at the spaces so no word ever snaps in half.
With a limit of 100 and numbering at the end, the splitter returns 2 tweets:
| Tweet | Content | Characters |
|---|---|---|
| 1/2 | A thread is just one idea broken into bite-sized posts. Write the whole thing first, then let 1/2 | 97 |
| 2/2 | the tool cut it at the spaces so no word ever snaps in half. 2/2 | 64 |
Notice that the first tweet stops right before “the”: the whole word moves to tweet two instead of being cut. The four characters of 1/2 are already included in that count of 97. Bump the limit up to 280 and the same text fits in a single tweet.
Frequently asked questions
Does it cut words in half?
No. The split always honours the spaces between words. The only time it chops anything is when a single “word” with no spaces — like a 300-character URL — is already longer than the entire limit, in which case there is no choice but to break it.
Does the 1/n numbering count toward the limit?
Yes, and that is why it matters. Each 1/n uses real characters inside the tweet. The splitter reserves that space before dividing and recomputes the total, so a tweet with its label never goes over the limit you set.
Can I use it for Threads, Bluesky or Mastodon?
Absolutely. Just change the “characters per tweet” number: 500 for Threads or Mastodon, 300 for Bluesky, 280 for free X. The packing logic is identical across all of them.
Is my text uploaded anywhere?
No. All the work happens in your browser with JavaScript; the text never leaves your device. You can even go offline after the page loads and it will keep working.
How does it count emoji?
Each emoji counts as one character (one Unicode code point). Keep in mind that X internally weights some emoji as two, so on very tight posts it is wise to leave a little headroom.