About comparing JSON
JSON Diff compares two JSON objects and shows exactly what changed between them — which keys were added, which were removed, and which values changed (with the old and new value). It flattens nested objects so you can see changes at any depth by their full path. It runs entirely in your browser.
How JSON Diff works
How to compare JSON
- Paste the original JSON on the left and the changed JSON on the right.
- Click Compare.
- Read the colour-coded list: green added, red removed, amber changed.
Nested keys
Objects are flattened to dotted paths (for example address.city), so a change deep inside an object is shown clearly with its full key path.
When it helps
Great for spotting differences between API responses, config files, snapshots or any two versions of structured data.
Common uses
- Compare two API responses
- Spot config-file changes
- Diff JSON before and after an edit
- Review data changes in a PR
- Debug unexpected JSON differences
- Compare snapshots
- Audit settings between environments
- Verify a transformation
Frequently asked questions
How do I compare two JSON objects?
Paste each into a box and click Compare — added, removed and changed keys are listed.
Does it handle nested objects?
Yes — nested keys are shown by their full dotted path.
What do the colours mean?
Green is added, red is removed, amber is a changed value.
Must the JSON be valid?
Yes — both inputs must parse as valid JSON.
Is my data uploaded?
No — the comparison runs entirely in your browser.
Does it compare arrays?
Arrays are compared as values at their key; element-level array diffing is not split out.
Can it show equal objects?
Yes — it tells you when there are no differences.
Is it free?
Yes — completely free with no sign-up.