Text Diff Checker
Compare two blocks of text line by line and see exactly what was added, removed or left unchanged.
100% private — everything runs in your browser
How to Use
- 1
Paste the original text into the left panel.
- 2
Paste the updated text into the right panel — the diff updates as you type.
- 3
Green lines were added and red lines were removed; copy or download the result.
Examples
One changed line
Input
Hello world → Hello there worldOutput
1 line removed, 1 line addedTwo added lines
Input
A three-line config → a five-line configOutput
2 added, 3 unchangedFAQ
How is the comparison calculated?
The tool finds the longest common subsequence of lines, so unchanged lines stay aligned and only real additions or deletions are highlighted.
Does it compare words or whole lines?
Whole lines. A small edit inside a line shows up as one removed line plus one added line, which keeps the result easy to scan.
Is my text uploaded anywhere?
No. The diff runs entirely in your browser and the text never leaves your device.
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