Why does it say lines were matched by position?

Full comparison holds a table proportional to the two line counts, so above 2,000 lines it falls back to comparing line by line in order. Still useful, but an inserted line will make the rest look changed.

Can it compare word by word instead of line by line?

Not currently — the comparison works on whole lines. For prose, putting each sentence on its own line before comparing gives a much more readable result.

Text Diff Checker

Paste two versions of a text and see precisely what changed. Lines that were added are marked with +, lines that were removed with -, and everything unchanged is shown for context. The comparison uses a longest-common-subsequence match, so a line inserted near the top does not make every line after it look changed.

Your text

Changed text

Ignore case

Ignore leading and trailing spaces

Ignore blank lines

Result

Nothing is uploaded — this tool runs inside your browser, so your files never leave your device.

Help us improve

Why use this tool

Proper LCS matching — an inserted line doesn't shift everything below it
Ignore case, surrounding spaces or blank lines while comparing
Counts exactly how many lines were added and removed
Comparison happens in your browser, so confidential drafts stay private

How it works

1Paste the original text into the first box.
2Paste the changed version into the second box.
3Read the result — + is added, - is removed.

Text Diff Checker — frequently asked questions

No. The comparison runs in your browser, which is why this is safe to use on contracts, drafts and anything else confidential.

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