Developer Tools
JSON Diff
Paste two JSON documents and instantly see what changed. OpenToolLab's JSON diff highlights added, removed, and modified fields with their exact paths — perfect for reviewing API responses, config changes, and migrations. Everything runs in your browser.
What makes this tool different
Structural JSON diff
Compares by key path, so reordered keys don't show as differences — only real value changes do.
Added / removed / changed
Every change is tagged and shown with its path, so you immediately know what to update in your code.
Plain-text line diff
Flip to line-diff mode for raw text, logs, or config files that aren't valid JSON.
Private by default
Both documents are compared in your browser. Nothing is uploaded, stored, or logged.
About this tool
JSON Diff: everything you need to know
Reviewing two versions of a JSON payload by eye is slow and error-prone. Whether you are debugging an API response, checking a config change, or reviewing a database migration, you need to know exactly which fields changed — not just that the text looks different.
OpenToolLab's JSON diff compares the two documents structurally. It walks each object by key path, so reordered properties don't create false positives, and it reports every addition, deletion, and value change with the precise path (for example user.address.city). That makes the output directly actionable in code.
For input that isn't valid JSON, the tool also offers a plain-text line diff powered by a longest-common-subsequence algorithm. This covers config files, logs, and source code where you just need to see added and removed lines.
Everything runs in your browser. The two documents are parsed and compared locally, so sensitive payloads are never uploaded, stored, or logged — which matters when you are diffing production API responses or customer data.
FAQ
JSON Diff — frequently asked questions
How do I compare two JSON files online?
Paste the original JSON in the left box and the modified JSON in the right box. OpenToolLab's free JSON diff tool computes the structural difference instantly and lists every added, removed, and changed field with its full path — no uploads, no signup.
Does the JSON diff ignore key order?
Yes. The structural diff compares by key path, so reordered keys do not show as changes — only real added, removed, or modified values are reported. That is the json diff online ignore order behavior you want.
Is this a free JSON difference checker?
Yes. OpenToolLab's JSON online diff checker is completely free, requires no signup, and runs 100% in your browser. It works as both a json compare online tool and a json difference online viewer.
Can I share a JSON diff with someone?
Yes. Use the Share button on the tool — it copies a link with your two documents encoded in the URL, so the person you send it to sees the exact same comparison. This covers the json diff online share workflow.
Can the JSON diff handle large files?
It compares entirely in your browser, so there is no server upload size limit. Very large JSON is limited only by your device's memory, but typical API responses and config files compare instantly.
How do I compare JSON and show the difference or merge changes?
Every change is listed with its full key path (added, removed, changed). Copy the diff to your clipboard and apply it wherever you merge — the tool shows the difference clearly so merging is straightforward.
What is the best JSON compare tool or Beyond Compare alternative for JSON?
A good JSON compare tool works locally (no uploads) and diffs by key path rather than raw text. OpenToolLab's tool is free, client-side, and shows changes by path — a browser-based alternative to desktop tools like Beyond Compare for JSON.
How do I diff JSON in Python or with a library?
In code you would use a library (for example deepdiff or json-diff) or write a recursive compare. This online tool does the same structural comparison in the browser with no install — paste two JSON documents and compare instantly.
Keep exploring