Text Diff Checker
Compare two texts line by line and see exactly what was added or removed.
+2 added · -1 removed · 2 unchanged
How to use Diff Checker
- 01Paste the original text on the left and the changed version on the right.
- 02The comparison runs as you type and marks each line as added, removed or unchanged.
- 03Switch between side-by-side and unified view, and read the totals at the top.
About Diff Checker
The comparison uses a longest-common-subsequence algorithm, the same approach behind the diff in version control tools. Instead of comparing line one to line one, it finds the largest set of lines that appear in both texts in the same order, so inserting a paragraph shifts nothing after it.
Because it works line by line, reformatting can look like a large change even when the words are identical. Comparing text that wraps at the same width, or removing trailing whitespace first, gives a much cleaner result.
Frequently asked questions
- Is my text uploaded anywhere?
- No. The comparison happens entirely in your browser.
- Can it compare code?
- Yes. Line-by-line comparison suits code, config files and prose equally.
- Why is a whole paragraph marked changed?
- The diff works on whole lines, so any edit within a line marks that line as changed.
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