diffesq.

Semantic JSON diff — compare two JSON files by meaning

A semantic JSON diff compares two JSON files by structure and value, not by text — so reformatting, whitespace, and reordered object keys don't register as changes. Diffesq runs that comparison locally in your browser and anchors each difference back to its position in the source file.

Diff two JSON files

How it works

  1. Drop a JSON file on each side of the workbench.
  2. Diffesq parses both documents locally and compares their structure.
  3. Review real value and structure changes — additions, removals, modifications — each anchored to its location in the source.
  4. Export a report generated on your device.

What the comparison covers

  • Structure-aware comparison: formatting-only edits are not reported as differences.
  • Source anchoring: every reported change points at its position in the file.
  • Tolerant parsing (comments and trailing commas via a JSONC-capable parser).

Free vs Pro

Structured-file comparisons run in full on your device on the free tier, with about a third of the results shown as a preview; Pro unlocks the complete results and clean, unwatermarked exports (HTML, Markdown, JSON, PDF).

See Pricing for plans — $2.97/month, $27.99/year, or $49 once.

Privacy

Every comparison runs locally in your browser. Your files are never uploaded — there is no server that receives them, and the page keeps working with Wi-Fi turned off. Details in the Privacy Policy.

Frequently asked questions

What makes a JSON diff 'semantic'?

It compares the parsed data, not the characters. Two files that decode to the same values are reported as identical even if their text differs — and a one-character value change is reported precisely, not as a wall of reflowed lines.

Is this safe for API payloads and configs with secrets?

The files are parsed and compared on your device and never uploaded, so secrets in a config never travel anywhere.

Does it work offline?

Yes — once the page has loaded, parsing, comparing, and rendering all happen on your device. Turn off Wi-Fi and it still works.

Do I need an account?

No. Comparisons run without any signup. Pro features unlock with a license key — still no account or login.

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