JSON Diff
Compare two JSON documents and highlight the differences.
Processed locally in your browser. Nothing you enter is uploaded or stored.
- Re-formats both sides identically first, so key order and whitespace don't create false diffs.
- Line-by-line highlight of added and removed values.
- Runs in your browser; neither document is uploaded.
Why this is private
- Processed locally in your browser. Nothing you enter is uploaded or stored.
- Open your browser's DevTools → Network tab while using this tool — you won't see a request carrying your input, because it never leaves your device.
- Nothing you enter is uploaded to a server or shared with us — the processing happens entirely on your device.
Overview
Compares two JSON documents by formatting both consistently and diffing them line by line — useful for spotting what changed between two API responses or config versions.
How to use it
- 1Paste the original JSON on the left.
- 2Paste the changed JSON on the right.
- 3Both are parsed, re-formatted identically and diffed so unrelated whitespace or key-order changes don't create noise.
Tips
- Differences in formatting or key order alone won't show up as changes — only actual value or structure differences will.
Frequently asked questions
What people use it for
See what changed between two API responsesDiff a working response against a failing one to find the differing field.
Compare config across environmentsSpot the setting that differs between staging and production JSON.
Review a JSON fixture updateConfirm a test fixture change only touches what you intended.
Check a migration's outputDiff a record before and after a transform script.
Related guides
- How to format JSON (and actually understand the errors)JSON looks like a JavaScript object but follows stricter rules. Here's what those rules are and how to read the errors when they're broken.
- How to read JSON with a tree viewerA tree viewer turns a wall of brackets into a structure you can expand, search and copy paths from. Here's how to use one effectively.
- JSON parse errors explained: 'Unexpected token', 'Expected comma or brace', and the restWhat each common JSON error message actually means, the usual cause, and how to find the spot fast using line and column.
Related tools
All developer toolsJSON Viewer & FormatterView, format, validate, edit and beautify JSON with an interactive tree view, plus a shareable link.JSON ValidatorValidate JSON syntax and pinpoint errors instantly.Text Diff CheckerCompare two blocks of text at line, word or character level, with an ignore-whitespace option.JSON MinifierStrip whitespace to compress JSON to its smallest size.
Ready to use JSON Diff?
JSON Diff