JSON Diff

Compare two JSON documents and see exactly what changed.

ToolsSoup's JSON Diff is a free online tool that compares two JSON documents and highlights exactly what changed — every added, removed, and modified value, each with its full path. Paste an original and a changed version, click Compare, and read a clear, color-coded list of differences. Everything runs in your browser and nothing is ever uploaded.

What is a JSON diff tool?

A JSON diff tool compares two JSON values and reports the differences between them. Instead of squinting at two files side by side, you get a precise list: which keys were added, which were removed, and which values changed, each labelled with its path such as user.address.city or items[2]. Developers use it to review API changes, compare configuration files, and confirm that an edit did exactly what they intended.

How to compare two JSON files online

Comparing JSON with ToolsSoup takes just a few seconds:

  1. Paste the original JSON into the left box and the changed JSON into the right box.
  2. Click Compare to run a deep, key-by-key comparison of the two documents.
  3. Review the color-coded results — additions, removals, and changes — and copy the diff if you need it.

How JSON differences are detected

The tool parses both sides and walks them recursively. Objects are compared by key, arrays by position, and values by deep equality, so nested structures are compared all the way down. A difference is reported only when the underlying data actually changes — reindenting or reordering the keys of the same JSON produces no differences at all.

Why use this JSON diff tool?

  • 100% free with no ads, sign-up, or usage limits.
  • Runs entirely in your browser — your data is never uploaded to a server.
  • Deep comparison of nested objects and arrays with full key paths.
  • Color-coded additions, removals, and changes that are easy to scan.
  • Works offline once the page has loaded.

Frequently asked questions

Is this JSON diff tool free?

Yes. Every tool on ToolsSoup is completely free to use, with no account, sign-up, or hidden limits.

Does the order of keys affect the comparison?

No. Objects are compared by key name, so the same keys in a different order count as identical. Arrays, however, are compared by position, because order is meaningful in a JSON array.

Can it compare nested objects and arrays?

Yes. The comparison is recursive, so differences inside deeply nested objects and arrays are found and reported with their full path, such as user.roles[0].

Why does reformatting my JSON show no differences?

Because the tool compares data, not formatting. Whitespace, indentation, and key order do not change the underlying values, so reindented or minified JSON with the same content shows as identical.

Is my JSON data safe?

Absolutely. All comparison happens locally in your browser using JavaScript, so your JSON is never sent to or stored on any server.