{ }
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Format, validate, and minify JSON with syntax highlighting.
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JSON Diff Checker
Compare two JSON objects and highlight what changed.
json-diff.tool
Click Compare to see what changed
Nothing you paste here is ever sent to a server - the comparison happens locally in your browser.
What is a json diff checker?
A JSON diff checker compares two JSON values and shows exactly what changed between them - keys that were added, keys that were removed, and values that changed - without being tripped up by superficial differences like key order. It's the fastest way to understand what actually moved between two versions of a config file, API response, or state snapshot.
How to use this tool
- 1Paste the original JSON into the left box, and the updated version into the right box.
- 2Click Compare.
- 3Each difference is listed with its exact path in the object, color-coded: green for added, red for removed, amber for changed.
- 4For changed values, both the old and new value are shown side by side.
Common use cases
Reviewing what changed in a config file before deploying it
Comparing two versions of an API response to debug unexpected behavior
Checking whether a script or migration modified data as intended
Understanding a large JSON payload by diffing it against a known-good baseline
Good to know
Frequently asked questions
Does key order matter?
No. Two objects with the same keys and values in a different order are treated as identical - the comparison is based on structure and values, not the order keys were written in.
How are arrays compared?
Arrays are compared index by index. If an array grows or shrinks, the extra or missing items are reported as added or removed at that index; if an item at the same index changes, it's reported as changed at that path.
What does a path like user.tags[2] mean?
It's the exact location of the difference: the tags array inside the user object, at index 2. This lets you find the change in a large document without searching manually.
Is either JSON file uploaded anywhere?
No. Both files are parsed and compared entirely in your browser - nothing is sent to a server.
quick_facts.json
{
"runs_in_browser": true,
"data_sent_to_server": false,
"signup_required": false,
"price": "free",
"category": "JSON Tools"
}