Free tool · Developer utilities
Compare two texts
Paste two versions to see what changed, line by line with the changed words highlighted.
Runs in your browser. Nothing you paste is uploaded.
About this tool
Diff checker: how it works
Support teams use this to review edits to canned responses, macros and help articles before they go live. Developers use it for config files and API responses. The diff updates as you type.
It uses the Myers algorithm, the same approach as git diff, so adding one line at the top shows one added line instead of marking the whole rest of the text as changed. When a line is edited, the exact words that changed are highlighted on both sides.
Turn on Ignore whitespace to skip indentation and trailing space changes, which is handy after reformatting. For JSON, format both versions first with the JSON formatter so key order and spacing match.
What it does
- Real line diff, insertions do not shift everything below
- Word highlights inside changed lines
- Unified or side by side view
- Ignore whitespace and ignore case
- Only changes view with 3 lines of context
- Copy or download as a .diff
Building on Ticketdesk?
Automate tickets, AI agents and inboxes from your own code.
FAQ
Diff checker: common questions
How do I compare two texts?
Paste the original on the left and the new version on the right. Added lines are green with a +, removed lines are red with a -, and the changed words inside a line are highlighted.
Can I see only the changes?
Turn on Only changes. Unchanged lines are hidden except for 3 lines around each change, like a code review.
Is there a size limit?
There is no file size limit, but if more than 4,000 lines differ the texts are treated as unrelated and not diffed. Normal edits to long documents are fine.
Is my text uploaded?
No, the comparison runs entirely in your browser.