JSON compare & merge
Paste two JSON documents to see a line-level diff and a structured list of every added, removed, or changed field — then merge the two into a single result.
Compare, understand, and merge — not just diff
Most JSON diff tools stop at highlighting text. This one also gives you a structural list of exactly what changed and lets you build a merged result.
Frequently asked questions
What's the difference between the visual diff and the differences list?
The visual diff highlights changed lines in the pretty-printed text of both documents, like a code diff. The differences list is structural — it walks the actual JSON values and reports each added, removed, or changed field by its exact path, which is more precise for nested data.
How does the merge feature work?
Starting from the left (original) document, click "Keep Left" or "Keep Right" on any difference to build a merged result. Once you've resolved the differences you care about, copy or download the merged JSON.
Is my data uploaded to compare it?
No. The comparison and merge both run entirely in your browser — neither document is ever sent to a server.