Diff Checker
Paste two versions of text on the left and right. The tool highlights every line that was added, removed, or changed between them.
What this tool does
- Line-by-line comparison with added, removed, and unchanged lines marked
- Side-by-side view that lines up matching content
- Counts of how many lines were added and removed
- Compares locally — paste contracts, code, or drafts safely
Also known as: text compare, compare two texts, text difference tool.
Frequently asked questions
How does it match up lines?
It uses a longest-common-subsequence diff — the same core algorithm Git and most diff tools use — to find the largest set of unchanged lines, then marks the rest as added or removed.
Does it compare word by word?
The comparison is line by line, which is what you want for documents, configs, and code. A changed line shows as one removal plus one addition.
Is my text private?
Yes. Everything runs in your browser with JavaScript — nothing you type or paste is uploaded, logged, or sent to a server. You can disconnect from the internet after the page loads and it still works.
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