JSON Diff

Both editors highlight JSON, number the lines and keep indentation, and the offending line number turns red; clicking the error jumps the caret to it. Format re-indents that side with two spaces so the two documents line up. This is a structural comparison, not a text one: objects are compared by their key set, so a different key order is not a difference, and arrays are aligned by element content, so inserting an item in the middle does not flag everything after it. Elements the alignment could not match are then paired up in order and compared recursively, which turns “one field of one list item changed” into a path you can jump to, such as $.items[0].name. If either side has a syntax error no change list is produced at all — only the offending line and column, so you are never debugging against a misleading result.