JSON Diff
JSON Diff expands on the amazing work by the guys at jsonlint.com and provides a semantic compare tool for JSON documents.
I often work with large documents and it's difficult to see the differences between them. Normal text compare tools work well for finding the differences in JavaScript code, but JSON data can have many differences in the text that don't actually change the data.
JSON Diff sorts, formats, and compares two JSON documents to find the actual semantic differences instead of just the text ones.
Try it out: http://www.jsondiff.com
Run the built-in unit tests: http://www.jsondiff.com/index-test.html