JSON Diff Checker
Compare two JSON documents and instantly see every added, removed, changed, and type-changed field. Supports nested objects, arrays, type changes, and full dot-notation paths.
How to use JSON Diff Checker
Frequently Asked Questions
How does array comparison work?
Arrays are compared index-by-index. If item 1 changes and item 2 is added, you'll see items[1] changed and items[2] added. Full path is always shown.
What's the difference between null and a missing key?
They're treated differently. A key set to null is shown as 'changed' if the other side has a different value, and 'removed' if the key doesn't exist at all on the other side.
Does type change detection work?
Yes. If a value changes from a number to a string (e.g. 30 → "30"), the tool shows TYPE CHANGED with both the old and new types.
Is there a size limit?
There's no hard limit, but very large documents (1MB+) may slow the browser. The comparison only runs when you click Compare, not on every keystroke.
Are my API keys and secrets safe?
Yes — everything runs in your browser using JavaScript. No data is sent to any server, API, or analytics service.