Diff Checker
Compare two text blocks.
100% private Runs locally No sign-up
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Heavy libraries load on demand so the page shell stays fast.
About Diff Checker
Diff Checker compares two text blocks side by side in the browser — config files, policy drafts, or API payloads — without uploading either side to a cloud diff service.
How to use Diff Checker
- 1Paste the original text in the left panel.
- 2Paste the modified text on the right.
- 3Review highlighted additions and deletions.
- 4Copy the kept version into your editor or docs.
Frequently asked questions
Binary files?
This tool is for text. Use Document Compare for richer document workflows where available.
Word-level vs line-level?
Highlighting follows the UI’s diff granularity. Huge single-line minified files are harder to read — prettify first.
Privacy?
Both sides stay local. Still avoid pasting live production secrets.
Merge conflicts?
The checker visualizes differences; it does not auto-merge three-way Git conflicts.
JSON diffs?
Pretty-print with JSON Formatter first so structural changes are clearer.
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