Google is one of the main reasons that JSON-LD Schema has become so important. Therefore, Google is one of the best resources for testing that schema with the Google Structured Data Testing Tool.

JSON-LD.org has a viewer and debugger to help you play with JSON-LD. If you’re interested in learning the programming language, this site will be a great resource for you to learn and share your code.

Schema.org has a goal to create, maintain & promote schemas for use on the internet to organize and connect data. Schema.org is sponsored by Google, Microsoft, Yahoo and Yandex and includes schema vocabulary the can be used in RDFa, JSON-LD and Microdata.