How do I compare two JSON files and see only the real differences?

Paste or drop the original into Original (A) and the changed version into Changed (B). The tool compares structure rather than lines and lists each change by path as added, removed or changed. Formatting and key order do not create differences.

Why does reordering an array show up as lots of changes?

By default arrays are compared by position, so a reorder changes many indexes. Under Arrays, choose Match by id/key to pair objects by a shared id field, or Ignore order to treat arrays as unordered sets.

Can I ignore fields like updatedAt or timestamps when diffing JSON?

Yes. Open the options and type comma-separated names in Ignore keys, for example updatedAt, timestamp, id. You can also ignore case in text and treat 1 and the string "1" as equal.

Why do I get an error about unexpected characters in my JSON?

The message gives the line and column of the problem, and Go to error jumps to it. If the input is near-JSON, with trailing commas, comments, single quotes or unquoted keys, the Fix automatically button rewrites it as standard JSON.

Can I export the differences as a JSON Patch or unified diff?

Yes. Pick Export format: Change log, JSON Patch (RFC 6902) or Unified diff. The patch is an exact, position-based comparison, so the ignore options and array matching do not apply to it.

Yes. Every tool is free to use, with no account and no credit card. The work runs on your device rather than on our servers, which is what keeps it free to run.

Does it work on mobile?

Yes. It runs in current mobile browsers on iOS and Android, with nothing to install.

🔀

Free JSON Diff

Compare two JSON objects structurally — see exactly which keys were added, removed, or changed, even deep inside nested data. Runs in your browser.

Runs in your browserNo sign-up, no pop-upsNo login requiredFree forever

Works offline once loaded

Original (A)

You can also drop a .json file here.

Changed (B)

You can also drop a .json file here.

Arrays:Compares elements position by position — a reorder shows as many changes.

Options: ignore keys, case, types, sort keys

Ignore keys (comma-separated)

Ignore case in textTreat 1 and "1" (and true and "true") as equalSort keys (Format and side-by-side view)

💡 A structural diff (not line-by-line): it walks both objects and reports exactly which paths were added, removed, or changed — even deep inside nested objects and arrays. Everything runs in your browser.

Common uses

Compare Two API ResponsesSee exactly what changed between two JSON API responses.
Compare Config FilesDiff two JSON configs to find what changed between environments.
Debug Unexpected JSON ChangesPinpoint why a JSON object isn't what you expected.
Compare Two Versions of a DocumentDiff two versions of a JSON document or data export.
Review JSON Changes in a PRUnderstand a JSON change more clearly than a line diff.

How It Works

A line-by-line diff is noisy for JSON because formatting and key order change. This compares the two values structurally and tells you exactly what changed.

1
You paste two JSON values
An original (A) and a changed (B). Both are parsed locally — nothing is uploaded.
2
They're compared by structure
The tool walks both trees recursively, matching keys and array indices regardless of formatting or key order.
3
Differences are listed by path
Each change is reported with its exact path (e.g. user.roles[1]) as added (+), removed (−), or changed (~) with the old → new value.
4
You see a clear summary
Counts of added/removed/changed, then the detailed list — or confirmation that the two are identical.

API responses and config can be sensitive. The comparison runs entirely on your device — neither value is uploaded.

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