JSON Diff

JSON Diff delivers exactly what its name promises, semantic, order-independent diff of two JSON documents: added, removed and changed values by path, fast and free. Because it belongs to ToolsMonk's developer tools collection, the whole workflow happens on a single page instead of being spread across separate apps or websites.

Typical jobs it handles include comparing two api responses or config versions, reviewing what changed between two json snapshots, and spotting accidental key removals or type changes. The same page works on desktop, tablet, and mobile, so it is equally quick for a single urgent task and for work you repeat every week.

It is built for getting a real result on the first visit: no learning curve, no account, and the wider ToolsMonk toolbox close at hand.

JSON Diff compares two JSON documents by meaning rather than by text. It lists every added key, removed key, changed value with its old and new version, and change of type, each grouped under its path, with colour coding and a count of each kind of change.

Because it is semantic, the order of keys in an object is ignored: two configs that contain the same data in a different order are reported as identical, which a plain text diff gets wrong. For arrays you choose: keep order comparison on for ordered lists, or switch it off when the array is really a set.

Both inputs are validated first, and an invalid document is reported with its error position, so a stray comma cannot masquerade as a difference.

It is ideal for comparing two API responses, two versions of a configuration file, or the before and after of a refactor, and especially for catching a key that was dropped or a number that quietly became a string.