Don's Tools · Text & Writing · Text Compare & Diff

Text compare & diff

See exactly what changed between two versions of your text, right in your browser. Nothing is uploaded.

Private by design: both texts are compared in your browser and are never uploaded. The diff is line by line: lines only in A are removed (red), lines only in B are added (green), and unchanged lines are grey.
Text Compare and Diff is a free tool that shows the differences between two versions of text entirely in your browser, with nothing uploaded. Paste an original and a changed version and it compares them line by line, marking removed lines in red, added lines in green and unchanged lines in grey, with options to ignore case and whitespace. You can copy or download the resulting diff.

Frequently asked questions

Is my text uploaded anywhere?

No. Both texts are compared entirely in your browser and are never sent to a server.

How does the comparison work?

It compares the two texts line by line and finds the smallest set of changes. Lines only in the original are marked as removed in red, lines only in the changed version are added in green, and matching lines are shown in grey.

What do Ignore case and Ignore whitespace do?

Ignore case treats capital and small letters as the same, and Ignore whitespace ignores differences in spaces and tabs, so only real content changes show up. Your original text is still displayed unchanged.

Can I save the differences?

Yes. After comparing you can copy or download the diff, where added lines start with a plus, removed lines with a minus, and unchanged lines are indented.

Does it compare word by word?

The comparison is line by line, which is clear and fast for documents, lists and code. A whole line that changed shows as one line removed and one added.

Is there a size limit?

Each side can be up to about 4000 lines. Larger texts are better compared in smaller sections so your browser stays responsive.