JSON Schema Specification

JSON Schema is a vocabulary that enables the confident and reliable use of the JSON data format for describing the structure and validation constraints of JSON documents. With over 60 million weekly downloads across npm, PyPI, and other package registries, it has become the de facto standard for JSON data validation, documentation, and interoperability. The specification is used by major technology companies including Microsoft, GitHub, Postman, Zapier, Oracle, Airbnb, and Stripe to validate API payloads, generate documentation, power form builders, and ensure data quality in streaming pipelines. JSON Schema provides three primary benefits: streamlining testing and validation by defining constraints that catch errors and prevent invalid data; enabling seamless data exchange by establishing a common language with precise validation rules across systems and platforms; and documenting data structures through clear, standardized representations that improve collaboration among developers and stakeholders. The project maintains a vibrant tooling ecosystem with validators, generators, linters, and utilities across virtually all programming languages. The JSON Schema specification is developed through an open community process with weekly office hours, monthly working meetings, an annual conference, and a Slack community of over 5,000 practitioners. Bronze sponsors include AsyncAPI, Oracle, Airbnb, n8n, and SourceMeta, with development funded through Open Collective.