Compare JSON Files Online
Compare two JSON files directly in your browser. See rows only in file A, only in file B, and rows common to both — no upload required.
File A
Drop your .json file here
or click to browse — max 50 MB
File B
Drop your .json file here
or click to browse — max 50 MB
About this tool
Compare two JSON files and see exactly what changed. The tool shows rows only in file A, only in file B, and rows common to both. All processing runs locally in your browser — no data is uploaded.
Frequently Asked Questions
How does the JSON file comparison work?
The tool performs a full outer join on all columns. It reports rows that appear only in file A, only in file B, and rows that are identical in both files.
Do both JSON files need to have the same columns?
Yes. Both files should have the same column names and compatible types for a meaningful comparison. If schemas differ, the join will still run but results may be misleading.
Can I compare large JSON files with many rows?
Yes, within your device's available RAM. The tool handles large set operations efficiently using optimised in-browser processing.
Is my data private?
Yes — completely. Your file is never uploaded to any server. Everything runs locally in your browser using WebAssembly — processing happens entirely inside your tab. Once you close the tab, nothing is retained.
What is the maximum file size?
The free limit is 50 MB. For larger files, performance depends on your device's available memory — most modern machines handle 500 MB to 1 GB comfortably.
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