Quickly compare two JSON objects and see exactly what changed—ideal for debugging APIs and configs.
All JSON processing happens locally in your browser. No data is uploaded or stored.
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This is the 'original' or 'expected' document. It can be a full JSON object, array, or any valid JSON value.
This is the 'modified' or 'actual' document. The diff shows what changed from left to right.
The tool parses both documents and shows a colour-coded diff: green for additions, red for deletions, yellow for changed values. Unchanged lines are collapsed by default.
Expand sections to see context around changes. Use the summary panel to see a count of: added keys, removed keys, and changed values.
Copy the diff report as text or export it as a JSON patch (RFC 6902 format) showing the minimal set of operations to transform document A into document B.
Common real-world scenarios where this tool saves time.
Back-end developers
Compare the JSON response from two API endpoints, two API versions, or before/after a code change. Instantly see which fields changed, were added, or were removed.
DevOps and infrastructure engineers
Compare JSON config files (package.json, tsconfig.json, AWS CloudFormation, Terraform plan outputs) between branches, environments, or deployment versions.
QA and test engineers
When an API test fails, paste the expected and actual JSON into the diff tool to see the exact discrepancy — faster than reading a raw test failure output.
Input
Left: { "status": "ok", "count": 5, "data": [1,2,3] } · Right: { "status": "ok", "count": 6, "data": [1,2,3,4] }Output
Changed: count 5→6 · Added in data: 4Quickly confirms that an API response changed only in the count field and data array — a single new record was added. No other fields were touched.
Input
Left: production.json · Right: staging.jsonOutput
Added: debug:true · Changed: log_level 'error'→'debug' · Changed: db_host 'prod-db'→'staging-db'Diffing environment config files reveals exactly which settings differ between environments, preventing configuration-drift bugs.
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In semantic mode (default), key order does not matter. {"a":1,"b":2} and {"b":2,"a":1} are considered identical. In strict mode, key order is respected and reordering counts as a change. Use semantic mode for comparing data; strict mode for comparing serialised payloads where order is significant.
RFC 6902 defines a JSON Patch format: an array of operations (add, remove, replace, move, copy, test) that describe how to transform one JSON document into another. Example: [{"op":"replace","path":"/count","value":6}]. JSON Patch is used in REST APIs for partial resource updates (HTTP PATCH method).
Yes. The diff recurses into nested objects and arrays. Array comparison is done by index — a change at index 0 shows as a change at [0], not a remove+add. Enable the 'unordered array' option to compare arrays as sets (ignoring order) when element order is not significant.
JSON diff shows what changed. JSON Merge Patch (RFC 7396) is a format for expressing updates: a Merge Patch document containing only the changed fields is applied to the original. It is simpler than JSON Patch but cannot express deletions easily (uses null for deletion). JSON diff tools can often export in either format.
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Reviewed by EverydayTools Editorial Team.