About Smart JSON Diff

Structural diff between two JSON docs with summary stats. Part of the DevTools Surf developer suite. Browse more tools in the JSON collection.

Use Cases

• Comparing staging and production API responses to spot differences
• Reviewing configuration changes between deployment versions
• Debugging unexpected data changes in webhook payloads
• Validating database migration outputs by diffing before and after snapshots

Tips

• Paste both JSON documents to see added, removed, and changed keys
• Review the summary stats for a quick change overview
• Use this to compare API responses between environments

Fun Facts

• JSON (JavaScript Object Notation) was formalized by Douglas Crockford in RFC 4627 in 2006, though it had been in informal use since 2001.
• The diff algorithm most commonly used in programming was published by Eugene Myers in 1986 in the paper 'An O(ND) Difference Algorithm and Its Variations.'
• JSON has only 6 data types (string, number, object, array, boolean, null), yet it became the dominant data interchange format, surpassing XML by 2013 in API usage.

FAQ

How does this compare to the JSON Diff tool?

Same structural comparison engine. 'JSON Diff' is the canonical name; 'Diff Two JSON' is an alias that ranks separately because users search for both phrasings.

Does it handle semantic equality?

Yes — key order doesn't matter, whitespace doesn't matter, and numeric precision respects JSON rules (1 equals 1.0). Use strict mode to require byte-identical values.

Can I see the exact path of each change?

Every added/removed/changed value is reported with a full path like `user.addresses[2].country`. Click to copy paths for use in follow-up queries.

Is there a line-count limit?

No hard limit — the comparison is streaming. For 50MB+ files performance degrades but output is still correct.