Diff checker
See exactly what changed between two versions of text or code, right in your browser. Nothing is uploaded.
Files are processed in your browser and never uploaded.
How to use Diff checker
Add your text
Type or paste your text into the input box. Everything is handled by your own browser, so nothing is sent to a server.
Set the options
Choose Ignore case, Ignore whitespace and Trim line ends. The options are visible from the start, not hidden until you paste something.
Run it and keep a copy
Press Compare them, Don to produce the result. Copy diff puts the result on your clipboard.
What this tool does
Line-by-line difference highlighting
Paste the two versions and the comparison is line by line, so you can see exactly which lines moved, changed or stayed the same.
Added and removed lines colour-coded
Added lines and removed lines are coloured differently, which is the fastest way to read a diff you did not write yourself.
Ignore case, whitespace and trailing spaces
Ignore case, Ignore whitespace and Trim line ends stop the differences you do not care about from burying the ones you do.
Copy the diff
Copy the diff to paste it into a message, a ticket or a commit note.
Works offline, no sign-up
The comparison runs in your browser, so neither version is uploaded and the page works with no connection.
Frequently asked questions
Is my text uploaded anywhere?
No. Both versions are compared entirely in your browser and are never uploaded, so even private code or documents stay on your device.
How does the comparison work?
It compares the two texts line by line using a shortest-edit algorithm. Lines only in the original are marked removed in red, lines only in the changed version are added in green, and matching lines are grey.
What do the ignore options do?
Ignore case treats capitals as the same, Ignore whitespace ignores differences in spaces and tabs, and Trim line ends ignores trailing spaces, so only meaningful changes show up.
Can I save the differences?
Yes. After comparing, copy the diff, where added lines start with a plus, removed lines with a minus and unchanged lines are indented.
Is there a size limit?
Each side can be up to about 4000 lines; larger inputs are best compared in smaller sections so your browser stays responsive.
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