JSON diff and compare
Put one document on the left, the other on the right, and see what changed. Both panes are editable and independently validated, so you can fix a document while comparing it.
Open the compare →Ignore the differences you do not care about
- Ignore key order. Two objects with the same entries in a different order are the same object as far as JSON semantics go, but a text diff will paint them entirely red and green. With this on, only genuine changes are highlighted.
- Ignore whitespace. Compare a minified response against a formatted fixture without every line registering as a change.
Both are toggles, so you can see either view without re-pasting anything.
Two layouts, one keystroke apart
Split shows the documents beside each other with changes aligned; unified stacks them as a single stream of additions and deletions, which is easier to scan on a narrow screen. ⌘⌥D switches between editing the panes and viewing the diff, and your caret position survives the switch.
Getting the documents in
Paste, drop a file onto either pane, or send the document you already have open in the editor to whichever side you want — useful for comparing a response you are inspecting against a known-good fixture. Each pane remembers its content between visits.
Questions
Can it compare JSON regardless of key order?
Yes. Turn on "ignore key order" and objects whose keys appear in a different sequence are treated as identical, leaving only real differences highlighted.
Does it do a semantic or a textual diff?
Textual, computed after optional normalisation for key order and whitespace. That keeps the output aligned with the text you are editing rather than an abstract tree you cannot see.
Are both documents uploaded for comparison?
No. The diff is computed in your browser. Neither document leaves your machine.
Can I edit while comparing?
Yes. Both panes are full editors with their own validation, and typing in the read-only diff view returns you to edit mode automatically.