What it does
The thread splitter packs your text into posts at the most natural break that fits (paragraph, then line, sentence and word), reserves room for the number marker, and repeats until the number of posts is stable.
How does the splitter decide where to break?
It fills each post as far as it can, then breaks at the most natural point that still fits. The order of preference:
- A forced break: a line with only
--- - A paragraph break (a blank line)
- A line break
- The end of a sentence
- A space between words
- Only as a last resort, inside a word longer than a whole post
Each post is measured with X's weighting, so emoji, links and non-Latin scripts are counted correctly.
How is the numbering kept inside 280?
The splitter reserves room for the widest marker before it packs the text. It doesn't know how many posts there will be until it has split, and "9/9" is shorter than "10/10", so it splits, checks the count, and splits again if the count crossed a digit boundary. It stops when the number of posts no longer changes.
| Style | Looks like | Notes |
|---|---|---|
| 1/5 | …end of post. 1/5 |
The most common; short |
| (1/5) | …end of post. (1/5) |
Easier to spot at a glance |
| [1/5] | …end of post. [1/5] |
Same idea, square brackets |
| 🧵 1/5 | …end of post. 🧵 1/5 |
Thread emoji on the first post only |
| 1. | 1. Start of post… |
Number at the start |
| none | For threads where numbering would distract |
Should a thread be numbered?
Numbering helps readers know how long they're signing up for, and makes it easy to quote "point 4". It can also feel mechanical for a story. The guide to writing threads covers when to use each, and how to write a first post that earns the rest.
A note on long posts
X Premium subscribers can publish posts far longer than 280 characters. If you have that and your readers do too, one long post may be better than a thread. Threads still reach everyone in their usual form and break up nicely for replies and reposts.
FAQ
How do I force a break in a particular place?
Put a line containing only three dashes (---) where you want the next post to start. Blank lines are treated as paragraph breaks, which the splitter prefers but won't force.
Why did the numbering style change the number of posts?
Markers take space. ' (10/12)' costs 8 characters against 4 for ' 1/5', and the splitter reserves room for the widest marker in the thread, so a long thread with brackets can need one more post.
Can it post the whole thread for me?
No. X's share link only opens a single post. Use Open in X on part 1, publish it, then reply to it with part 2 and so on, or paste the parts into X's own thread composer.
Does it ever cut a link in half?
No. A link is one unit worth 23 characters. Only a single word longer than a whole post (rare outside test strings) is ever cut mid-word.