Compare two blocks of text
Paste the original and the changed text side by side. See added, removed, and modified lines with character-level highlighting on changed lines.
Drop your file here
or click to browse
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How it works
Paste the original and the changed text side by side. See added, removed, and modified lines with character-level highlighting on changed lines.
The tool runs a longest-common-subsequence diff at the line level, then pairs up modified lines and runs a second character-level diff inside each pair. Equal lines show in both columns. Added lines (in the right column only) are highlighted green with a + marker. Removed lines (in the left column only) are red with a - marker. Modified lines show side by side with the changed characters within each line highlighted. Stats at the top: added, removed, changed, unchanged. Useful for proof-reading edits, comparing config files, spotting what changed in a contract, or auditing a copy-paste. Pure character comparison: whitespace and case differences count as differences. Both text boxes accept any size of input (within memory limits).
How to use it
- Paste the original text. Put the before version in the left box.
- Paste the changed text. Put the after version in the right box.
- Read the diff. Added lines show green, removed lines red, and modified lines highlight the exact changed characters.
- Check the stats. The counters at the top total the added, removed, changed, and unchanged lines.
Frequently asked questions
- Does whitespace count as a difference?
- Yes. Extra spaces, trailing whitespace, and tab vs space all show up as differences.
- Is the comparison case-sensitive?
- Yes. "Hello" and "hello" diff as a change. There's no ignore-case toggle in this version.
- Can I compare two files?
- Not directly. Open each file in another tool, copy its contents, paste into the two boxes.
- Is the text uploaded?
- No. The diff runs entirely in your browser.