What is JSON Schema?

JSON Schema is a vocabulary that allows you to validate, annotate, and manipulate JSON documents.

A JSON Schema is itself a JSON document and requires a third party library to validate data against it.

It is currently a draft IETF standard allowing consistent expectation from implementations based on the standard specification.

Vocabularies

Published vocabularies

• JSON Schema Core the basic foundation of JSON Schema
• JSON Schema Validation the validation keywords of JSON Schema
• JSON Hyper-Schema the hyper-media keywords of JSON Schema

Proposed vocabularies requiring discussion, feedback and review

• JSON Schema API API documentation keyword proposal
• JSON Schema UI the UI keywords for consistent UI generation proposal

Implementations

A list of implementations is maintained in the GitHub repository. The list of supported languages currently lists validators for:

ActionScript 3, C, C++, Clojure, Dart, Erlang, Go, Haskell, Java, JavaScript, .NET, PHP, Perl, Python and Ruby

There are also UI generators, data parsers, schema editors, documentation generators and IDE support.