JSON Diff
Paste two JSON documents and see what was added or removed, line by line. Object keys are sorted first, so a reordered object is not counted as a change. Everything runs in your browser, so your data is never uploaded.
How to diff JSON
- Paste the original JSON into the left box.
- Paste the changed JSON into the right box.
- Read the highlighted additions and removals below.
About comparing JSON
Comparing JSON by eye is error-prone, especially when keys are reordered or the documents are large. A semantic diff normalizes both sides — sorting object keys while preserving array order — then highlights only the lines that genuinely differ, so you see real changes instead of formatting noise.
This is useful for reviewing API responses, config changes and snapshot test output. Everything is computed in your browser, so the data you compare — which often contains real records — never leaves your device.
Frequently asked questions
How do I compare two JSON files?
Paste the original on the left and the changed version on the right. Added lines are highlighted green, removed lines red, with a count of each.
Does key order matter?
No. Both sides are re-serialized with sorted keys before comparing, so reordering the same keys shows no difference — only real value or structure changes appear.
What if my JSON is invalid?
The tool tells you which side failed to parse and why, so you can fix it before comparing.
Is my data uploaded?
No. The comparison runs entirely in your browser; nothing is sent to a server.