JSON All-in-One
JSON comparison tool
Free online JSON compare tool
Open or paste the Before JSON in the main tab. Open or paste the After JSON into a second tab, then compare them in the same local workbench.
Recent successful runs
Only settings and opaque source fingerprints stay in this browser. JSON and results are not saved.
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Before, After, and the comparison share one workbench with separate tabs. Opening the files is a streamed source operation; building a diff materializes both documents and can cost substantially more memory.
How to read the result
Differences in data, not formatting
Object key order and whitespace do not count as changes. Array positions do: inserting an item can shift later indexes. A number and a string are different values, and a missing field is not the same as a field set to null.
The comparison uses the product diff screen. Opening a large file does not guarantee that comparing two large trees is cheap; test the exact pair and watch the browser's memory use.
Pasted or selected JSON stays in your browser tab. The tool does not submit either document to our servers.