Diff Checker
Compare two text blocks side-by-side and highlight inline differences. Word- and line-level diff for code, JSON, config files, and prose — runs in your browser.
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How to Use Diff Checker
- 1Paste the original text in the left panel and the modified text in the right.
- 2Click "Compare" to see the diff.
- 3Toggle "Side by side" for a two-column view with changed words highlighted inline, or "Unified" for a single +/- column.
- 4Click "Download .patch" to save a unified diff, then use the provided commands to apply or revert it.
Frequently Asked Questions
What is the difference between line-level and word-level diff?
The line diff (LCS) decides which whole lines were added or removed. For lines that changed in place, the side-by-side view runs a second word-level diff so you see exactly which words differ highlighted inline, instead of the whole line lighting up.
What format is the .patch file?
It uses the standard unified diff format, compatible with git apply and the patch command.
How do I apply the patch?
Save the .patch file and run "git apply diff.patch" in your repository, or "patch -p1 < diff.patch" for non-git projects.
How do I revert a patch?
Run "git apply -R diff.patch" or "patch -R -p1 < diff.patch" to reverse the changes.
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