Free browser tool

JSON diff checker

Compare two JSON values and list added, removed, and changed paths.

Input and settings

How to use it

Compare JSON A and JSON B and list added, removed and changed paths. It is useful for API responses, configuration files and saved data when you need to see where the structure changed.

Paste JSON A and JSON B.
Run the comparison.
Review the added/removed/changed counts and each path, then download the diff JSON if useful.

Comparison: Walks JSON values by hierarchy
Paths: $.key and [index] style
Arrays: Compared by position/index
Output: Diff list can be downloaded as JSON

Changing name and adding active produces one changed and one added entry

{"name":"A","count":1} compared with {"name":"B","count":1,"active":true} marks $.name as changed and $.active as added.

Arrays are compared by index, not by detecting moved objects. Inserting one item near the beginning of an array can make many later positions appear changed.

Object changes are tracked by key path

Keys that exist on only one side become added or removed. Shared keys are compared recursively when their value types allow it.

A type change becomes one changed location

String→number or object→array is reported as a change at that path instead of pretending the two structures are directly comparable.

Array order matters

This is not an LCS or ID-aware move detector. Reordering or inserting elements can produce a large diff even when the same objects are still present.

Both inputs must be valid JSON

Comments, trailing commas and JavaScript object syntax are not accepted as standard JSON. Clean the source first when necessary.

The downloadable result is a diff report, not a patch format

It can be archived or processed by another script, but it is not an RFC JSON Patch document that can automatically be applied elsewhere.