Text Diff Checker
Compare two blocks of text and see exactly what changed.
About this text diff checker
Spotting the difference between two nearly identical documents by eye is a job humans are bad at and computers are good at. This compares them line by line and marks what was added, what was removed and what stayed the same.
It is the same longest-common-subsequence approach that powers the diff in version control, so it recognises that a block was moved or that one line changed rather than reporting everything after an insertion as different.
How to use it
- Paste the original text on the left and the new version on the right.
- Additions show green, removals red, unchanged lines stay grey.
- Turn on ignore-whitespace or ignore-case if formatting noise is drowning out the real changes.
- The summary counts how many lines were added, removed and changed.
Text Diff Checker — FAQ
Does it compare word by word or line by line?
Line by line, which is what you want for documents, code and configuration files. A changed line shows as one removal plus one addition.
Is my text sent to a server?
No. The comparison runs in your browser, so it is safe for contracts, code and anything else confidential.
Why do two identical-looking lines show as different?
Usually trailing whitespace or a different line ending. Switch on ignore whitespace to confirm.