DevCoreTools
JSON Tools

JSON Diff

Compare two JSON values side by side and quickly find added, removed, and changed fields. Validate, format, and inspect JSON differences.

JSON comparison guide

Left JSON

Paste the old, original, or expected JSON value.

Processed locally in your browser. Limit 5 MB per side Your input is processed in your browser and is not uploaded or sent to a server. Avoid pasting production secrets, access tokens, private keys, passwords, or sensitive customer data unless you understand the risk.

Right JSON

Paste the new, updated, or actual JSON value.

Ready to see what changed?

Compare both inputs now. The page will move directly to the highlighted results.

Paste JSON on both sides, then choose Compare JSON.

Comparison Result

Side-by-side JSON comparison

Ready to compare JSON

Paste JSON in both editors and select Compare JSON. Differences will appear in aligned left and right columns directly below.

JSON Diff Guide

Compare JSON structure and values online

Find precise JSON changes without uploading either document.

What is a JSON Diff tool?

A JSON diff tool compares two JSON values and highlights data that was added, removed, changed, or changed type.

How to compare JSON online

Paste old JSON on the left, paste new JSON on the right, click Compare JSON, then review added, removed, changed, and type-changed values.

Common JSON comparison use cases

Compare API responses, configuration files, webhook payloads, database documents, test fixtures, before-and-after debugging data, and release output.

JSON Diff vs JSON Formatter

JSON Formatter improves readability and indentation. JSON Diff compares two valid values to identify structural and data changes.

JSON Diff vs JSON Validator

JSON validation checks syntax. JSON diff comparison checks data differences after both inputs pass syntax validation.

How arrays are compared

Version 1 compares arrays by index. A value at items[2] is compared with the value at the same position in the other array.

Privacy

Comparison happens locally in your browser. Your JSON is not uploaded, stored, or sent to an external service.

JSON Diff FAQ

Is this JSON Diff tool free?

Yes, it is free to use.

Does this tool upload my JSON?

No. JSON comparison runs locally in your browser.

What does JSON Diff mean?

JSON Diff means comparing two JSON values to find what was added, removed, or changed.

Can this tool compare invalid JSON?

No. Both inputs must be valid JSON before they can be compared.

Does object key order matter?

No. Object key order does not affect this JSON comparison.

How are arrays compared?

Version 1 compares arrays by index, so changes are shown based on item position.

Can I compare API responses?

Yes. Paste one response on the left and another on the right to find differences.

Can I copy the diff result?

Yes. You can copy the summary, full report, or paths grouped by change type.

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