Data Utility
JSON Diff / Compare Tool
Compare two JSON values locally and see exactly which fields were added, removed, changed, or kept the same. Use it for API payloads, config files, test fixtures, and release diffs.
Detailed guide
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Read the JSON Diff / Compare Tool guideFrequently asked questions
Does this JSON diff tool upload my JSON?
No. The comparison runs locally in your browser and WebUtilsLab does not save or upload the JSON you paste.
Can I compare arrays and nested objects?
Yes. The tool compares nested objects and arrays, with arrays compared by index.
Does sorting keys change the JSON values?
Sorting keys only normalizes object key order before comparison. It does not change array order or scalar values.