About JSON Diff

Compare two JSON documents and show structural differences. Part of the DevTools Surf developer suite. Browse more tools in the JSON collection.

Use Cases

• Compare API responses between staging and production
• Detect unexpected changes in configuration files
• Validate data migration output against expected results
• Review schema changes between API versions

Tips

• Compare two JSON payloads to find structural differences
• Distinguish between added, removed, and modified fields
• Use the diff output to create migration scripts between versions

Fun Facts

• JSON comparison must handle type coercion carefully: the number 1 and the string '1' are different in JSON but equal in JavaScript's == operator.
• Comparing two 1MB JSON files element-by-element can involve millions of comparisons, making efficient tree-diff algorithms essential.
• RFC 7396 (JSON Merge Patch) provides a simpler alternative to JSON Patch but cannot represent explicit null deletions or array modifications.

FAQ

How is this different from a plain text diff?

A text diff compares characters. This tool compares JSON structurally — key order and whitespace are ignored, so a reordered object is reported as identical, not as a huge churn.

What counts as a change?

Added keys, removed keys, changed values, and type changes (e.g. string to number). Array changes are reported element-by-element; object changes are reported key-by-key.

Can I diff deeply nested JSON?

Yes — the diff recurses through every nested object and array and reports the full path to each change (e.g. `response.data.items[3].name`).

Does it generate a JSON Patch?

This tool shows human-readable diffs. For a machine-applicable patch (RFC 6902 format), use the JSON Patch tool.