Text Diff Checker
Compare two texts line by line and highlight what was added, removed and unchanged.
0 added · 0 removed · 0 unchanged
Compare two versions line by line
The Text Diff Checker compares an original and a changed version of your text and highlights exactly what moved between them. Added lines appear in green, removed lines in red, and unchanged lines stay neutral, so you can spot edits at a glance without re-reading both versions in full.
How the comparison works
The tool splits both texts into lines and runs a longest-common-subsequence algorithm — the same idea behind version-control diffs — to find the smallest set of additions and removals that turns the original into the changed version. Everything runs in your browser, so private text never leaves your device.
How to use the Text Diff Checker
- Paste the original. Put the first version of your text in the left box.
- Paste the changed version. Put the edited version in the right box.
- Read the highlighted diff. Green marks added lines, red marks removed lines, plain marks unchanged.
- Check the summary. See how many lines were added, removed and left unchanged.
Frequently asked questions
Does it compare word by word?
It compares whole lines, which suits documents, code and lists. Any change within a line shows as one removed line and one added line.
Is there a size limit?
There is no hard limit, though very large texts take longer because line diffing grows with the size of both inputs.
Are my two texts uploaded?
No. The comparison runs entirely in your browser and nothing is sent to a server.
Why are two similar lines shown as removed and added?
Line diffing treats any change inside a line as a full replacement, so a small edit appears as one red line and one green line.