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Preview of X-Split

X-Split by Mujtaba Jafri

Auto-splits long X/Twitter posts into sentence-boundary thread chunks. Just type past 280 characters — the sidebar appears with numbered chunks ready to copy. Free, zero setup, no API keys. (Split Twitter / X posts into threads automatically)

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Extension Metadata

Screenshots
Extension side panel Loads automatically, when limit is crossed, and stores the text until you re split by pressingbuttons for resplit, fill full length toggle, theme mode, and hide panelOptions to preview in extension tab
About this extension
X-Split turns long X/Twitter posts into clean, numbered threads — automatically.

HOW IT WORKS
- Install the extension
- Go to x.com and open the post button
- Type or paste your text past 280 characters in red
- A sidebar appears showing each chunk with a copy button
- Copy and paste each chunk into X's compose box

That's it. No buttons to click. No settings to configure. No accounts to create.

FEATURES
Smart splitting — Breaks at sentence boundaries (. ! ?) when possible, falls back to word breaks. Your threads read naturally, not chopped mid-word.

Auto-split on input — The sidebar appears as soon as your text exceeds 280 characters. Edit or delete text and it stays in sync.

URL-aware counting — URLs are counted as 23 characters (matching X's t.co behavior). The extension never splits a URL across two chunks.

Per-chunk numbering — Each chunk gets (1/5), (2/5) etc. Choose from parenthesis, brackets, or slash format in settings.

Fill mode — Optional toggle to maximize character usage per chunk. Off by default (clean sentence breaks preferred).

Re-split — Edit your text after splitting, click the button to re-split. Don't start over.

Dark mode — Follows your system preference automatically.

Collapsible sidebar — Click X to hide the sidebar. A floating tab stays on screen to reopen it when you need it.

Customizable — Click the extension icon in your toolbar to adjust max characters, numbering style, URL counting, and fill mode.

WHY X-SPLIT
- Free — No subscription, no API fees, no hidden costs
- Private — All processing happens in your browser. Zero data collection. No analytics.
- Lightweight — Vanilla JavaScript, zero dependencies, no build step
- Works inside x.com — No tab switching, no external editors

PRIVACY
X-Split does not collect, store, or transmit any personal data. All text processing is local. No third-party services. No analytics. No tracking.

Full privacy policy: https://mujtabaj30.github.io/x-split/privacy/
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Permissions and data

Required permissions:

  • Input data to the clipboard
  • Access your data for x.com
  • Access your data for twitter.com

Optional permissions:

  • Access your data for x.com
  • Access your data for twitter.com

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
Add-on Links
  • Copy add-on ID
Version
1.0.0
Size
17.71 kB
Last updated
4 days ago (24 Jun 2026)
Related Categories
  • Photos, Music & Videos
  • Social & Communication
Licence
MIT Licence
Privacy Policy
Read the privacy policy for this add-on
Version History
  • See all versions
Tags
  • social media
  • twitter
  • word counter
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