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Compare JSON. Catch breaking API changes.

Paste two JSON responses and instantly find removed fields, type changes, additions and changed values.

🔒 Your JSON stays in your browser. Nothing is uploaded to BreakDiff.

JSON responsesPaste or load an example to begin.

Before JSONAfter JSON

Ignore paths (comma-separated, e.g. $.timestamp, $.request_id) Array matching Match arrays of objects by a stable key to avoid false changes when items reorder.

More than a text diff

Breaking changes

Flags removed fields and type changes that may break API consumers.

Structural changes

Finds additions and nested differences using readable JSON paths.

Value changes

Separates ordinary data changes from structural contract changes.

How BreakDiff works

BreakDiff parses both JSON documents locally in your browser, walks nested objects and arrays, and classifies differences. Removed fields and changed value types are marked as potentially breaking.

No JSON payload is sent to our server. The comparison runs locally in your browser.

Read the guide: How to Compare Two JSON API Responses →