Diff Checker
Compare two blocks of text line by line
How it works
Paste an original and a changed version of any text. A line-level diff (using a longest-common-subsequence algorithm) highlights additions in green and removals in red, with line numbers and totals. Both inputs are stored in the URL so you can share an exact comparison.
Frequently asked
Is it a line diff or character diff?
Line by line: each line is treated as a unit, which is ideal for comparing code, config and prose.
Is my text private?
Yes — the comparison runs entirely in your browser. Text is only ever placed in your own URL if you choose to share it.
Can I swap the two sides?
Yes, the Swap button exchanges the original and changed inputs.