JSON Diff

What is JSON Diff?

JSON Diff performs a deep structural comparison between two JSON documents, identifying added, removed, and modified values at every nesting level. It displays changes in a color-coded tree view with green for additions, red for deletions, and yellow for modifications, showing both old and new values. The tool handles reordered object keys, array element changes, and type changes with precise path reporting.

API developers comparing response versions, QA engineers debugging test assertions, and DevOps engineers auditing configuration changes. The tool runs entirely in your browser — your data never leaves your device.

How to Use JSON Diff

1. Paste the original JSON document in the left panel
2. Paste the modified JSON document in the right panel
3. View the diff tree with color-coded additions, deletions, and modifications
4. Expand or collapse nodes to focus on specific sections of the diff
5. Copy the diff summary or individual changed paths for documentation

Common Use Cases

• Comparing API responses between staging and production to identify unexpected differences
• Reviewing configuration file changes before merging pull requests
• Validating that a database migration preserved all expected data by comparing before and after exports
• Detecting schema drift between API versions by comparing sample response structures
• Debugging test failures by comparing expected and actual JSON outputs

Pro Tips

• JSON object key order does not affect equality — the diff correctly ignores key reordering and only flags actual value changes
• For arrays, the diff compares by index position — if you inserted an element at the beginning, every subsequent element will show as changed. Sort arrays before diffing if order is not significant
• Type changes (string '123' to number 123) are flagged as modifications — these are common when data passes through different serialization layers and can cause subtle bugs

Why Use This Tool?

• Privacy-first: All processing happens locally in your browser. No data is transmitted to any server.
• No installation required: Works in any modern browser on desktop or mobile.
• Completely free: No account, no credit card, no usage caps.
• Fast and reliable: Powered by modern Web APIs for near-instant results.

Related Concepts

Learn more about related topics: RFC 6902 JSON Patch, Deep equality, Structural diff, JSON Merge Patch.

Frequently Asked Questions