Free Online JSON Diff & Compare Tool
Compare two JSON documents and instantly find added, removed, and modified values.
Result
Compare your documents to see changes.
Understand what changed between two JSON documents
JSON Diff compares an original document with a new version so you can inspect changes without searching through every field. Use it to review JSON objects, API responses and configuration snapshots.
Added, removed and modified values
For valid JSON, results identify fields added to the new document, fields removed from the original, and values modified at the same path. Old and new values appear together, with type changes called out when applicable.
Find changes by path and line
Structural results show paths into nested objects and arrays, along with source line and column locations where available. If either input is invalid JSON, the tool switches to text comparison with line references and highlighted changes.
How to compare JSON
- Paste the earlier version into Original JSON and the revised version into New JSON.
- Select Compare, or use Load Example to explore a sample comparison.
- Review the change counts, paths and old/new values. Check whether the result uses structural or text comparison.
- Use Copy Result or Download Result to save the differences for your review.
Useful checks for development and testing
Developers can inspect configuration edits before a release. Testers can compare expected and actual response data, while API engineers can investigate missing fields or changed value types between service versions. A diff helps locate changes; it does not determine whether they meet your API contract.
Comparison happens in your browser
The comparison service processes both inputs locally in your browser. It does not send the documents to a backend for comparison. Copying and downloading results are actions you control.
Frequently asked questions
Do indentation and object key order count as changes?
When both documents are valid JSON, comparison uses parsed values, so whitespace and object key order do not count as structural changes. In text comparison, differences in the source text can appear in the results.
How are arrays compared?
Array entries are compared by index, not by an ID field. Reordering items or inserting an item near the beginning can therefore produce several differences.
Can I compare incomplete or invalid JSON?
Yes. The tool reports input validity and falls back to text comparison. Correct the syntax in both inputs and compare again if you need field paths and structural results.