JSON Diff
Fixpio’s json diff tool compares two JSON documents by structure and lists every added, removed and changed value by its path — in your browser, so private API responses and config files never leave your device.
Compare JSON documents
Paste two versions below and see exactly what changed.
Why use this JSON diff tool?
Built for the moments two versions almost match.
Debugging API changes
When an endpoint’s output changes, diffing yesterday’s response against today’s shows exactly which field moved, vanished or changed type.
Config reviews without the squint
Two versions of a settings file stop being a wall of look-alike text: the list shows only what actually differs.
Honest about what it is
A structural comparison, not a text diff: key order and whitespace are ignored, because in JSON they carry no meaning.
About the JSON Diff tool
This json diff tool compares two JSON documents by structure rather than by lines of text. Paste the original on the left and the changed version on the right, press Compare JSON, and every difference is listed by its path through the document — version changed from 1 to 2, tools[2] added, free removed — so you can see what actually changed instead of scanning two similar-looking walls of text.
The distinction matters because JSON is not line-based. Two documents can hold identical data with their keys in a different order or their spacing reformatted, and a text diff will light up like a Christmas tree over nothing. This tool parses both documents and walks them properly: objects are compared key by key, arrays element by element, at any depth, and a value that changed type — a number that became a string, an object that became an array — is reported as a change, not missed.
Invalid input is handled plainly: if either side is not valid JSON, the tool says which side failed instead of producing a meaningless comparison. Very large documents are fine within your browser’s memory; the comparison is a single walk, not a server job, so there is no upload queue and nothing to wait for.
People use a JSON diff to check what an API changed between versions, to review config and settings files before deploying them, to verify that a data export matches its source, and to catch the one field a script quietly altered. In every case the text can be sensitive — tokens, user data, internal settings — which is why the comparison runs entirely in your browser.
Your JSON is never uploaded, stored or seen by anyone else: it is parsed and compared on your device, and closing the tab takes it with you. There is no sign-up and no usage limit.
Frequently asked questions
The questions people ask when two JSON files disagree.
How do I compare two JSON documents?
Paste the first document into the left box and the second into the right box, then press Compare JSON. Every difference is listed below with its path and marked Added, Removed or Changed. Two sample documents are pre-loaded so you can see the result immediately.
What do Added, Removed and Changed mean?
Added: the path exists only in the right-hand document. Removed: it exists only in the left-hand one. Changed: it exists in both, but the value differs — the list shows the left value and the right value side by side. Array items are compared by position, so tools[2] means the third element of the tools array.
Does key order matter?
No. JSON objects are unordered, so this tool compares by key, not by position or line. Reordering keys or reformatting the spacing produces no differences — only real changes to structure or values are reported. That is the difference between a JSON diff and a plain text diff.
What happens if my JSON is invalid?
The tool tells you plainly which side — left or right — failed to parse, and runs no comparison. The usual causes are a missing comma, an unquoted key or a trailing bracket; Fixpio’s JSON Validator and JSON Formatter can help clean the document up first.
Can it compare large JSON files?
Yes, within your browser’s memory. The comparison is a single recursive walk of both documents, so even deeply nested structures are handled quickly. Extremely large documents (tens of megabytes of text) may be slow to paste into a text box — that is a browser limit, not a limit of this page.
Is it safe to paste private JSON here?
Yes. The comparison runs entirely in your own browser — your text is never sent to a server, stored by us or seen by anyone else. When you close the tab, nothing of it remains, because it never left your device.