DIFF Checker
Compare two texts and see every difference highlighted word by word.
Original
Changed
How to use this tool
Paste both versions
Original text on the left, changed text on the right.
Compare
One click runs a word-level diff, right in your browser.
Review changes
Scan the highlights and check the added/removed word counts.
Frequently asked questions
How does the comparison work?
Your texts are split into words and compared with a diff algorithm that finds the smallest set of additions and removals. Removed words show in red, added words in green.
Is my text uploaded anywhere?
No. The comparison runs entirely in your browser with JavaScript. Nothing you paste ever leaves your device.
Is there a text length limit?
Very long texts (over ~50,000 characters each) switch to a faster line-based comparison automatically, so the page stays responsive.
Does it detect moved text?
A moved paragraph shows as removed in one place and added in another — that is how all word-level diff tools report moves.
What are the stats counting?
Words, where a "word" is any run of non-whitespace characters. Punctuation attached to a word counts with it.