JSON Compare is a semantic diff tool that identifies structural and value changes between two JSON payloads. Unlike standard text diffs that break when object keys are reordered, this tool understands JSON structure and provides a side-by-side view of exactly what was added, removed, or changed — regardless of key order.
Simple string-based diff tools (like `git diff`) struggle with JSON because the order of keys in an object does not technically matter. This comparator first parses both JSON strings into ASTs (Abstract Syntax Trees) or JavaScript objects. It recursively traverses the objects, matching identical keys regardless of vertical arrangement, and mathematically determining semantic mutations before rendering the precise visual differences.
No. JSON objects are unordered by specification, so the comparator parses both inputs into objects before comparing. If {"a":1, "b":2} is compared to {"b":2, "a":1}, it correctly reports zero differences — the key order does not matter.
Yes. The diffing algorithm traverses recursively, so changes buried inside nested objects or arrays are accurately highlighted. There is no practical limit on nesting depth.
Git performs line-by-line text comparison. Running a JSON formatter that changes indentation from 2 to 4 spaces makes Git report every line as changed, even though the data is identical. A semantic JSON comparison ignores whitespace and compares the parsed data structure instead.
The tool currently works by pasting JSON into the two editor panels. Open your JSON files in a text editor, copy the content, and paste it into the left and right panels.
No. The comparison runs entirely in your browser. Your JSON data never leaves your device, which makes this safe for comparing config files, environment variables, or other sensitive data.
Yes, completely free with no account required.
Tool workspace
Free JSON Compare tool online — instantly find the exact differences between two JSON objects or files. Side-by-side diff highlighting for APIs and config files. No login.
Input
JSON A: {"name":"John","age":30}
JSON B: {"name":"John","age":31}Output