Text Diff Checker
Compare two texts line by line and see exactly what changed — additions in green, removals in red. Fast, accurate and completely private.
Enter text in both boxes to compare.
Spot every change at a glance
Comparing two versions of a document, contract, email or snippet of code by eye is slow and error-prone. This diff checker lines the two up and marks every difference, so you can see what was inserted, deleted or left untouched without re-reading the whole thing.
How to use it
- Paste the original on the left and the changed version on the right.
- Read the highlighted result — green is added, red is removed, plain is unchanged.
- Toggle whitespace handling or swap the sides to refine the comparison.
Frequently asked questions
How does the text diff work?
Paste your original text on the left and the changed version on the right. The tool compares them line by line using a longest-common-subsequence algorithm and highlights added lines in green and removed lines in red.
What does 'ignore leading/trailing whitespace' do?
With it on, lines that differ only by spaces or tabs at the start or end are treated as identical, so you see only meaningful changes. Turn it off for an exact, character-perfect comparison.
Can I compare code or JSON?
Yes. The diff is line-based, so it works well for source code, configuration files, JSON, CSV, prose or any plain text.
Is my text private?
Completely. The comparison runs entirely in your browser with JavaScript — nothing is uploaded, logged or stored.