JSON Schema Validator
Validate a JSON document against a JSON Schema and see every violation with its JSON Pointer path: types, required keys, formats, patterns, enums and more.
Free · No sign-up · Your inputs stay in your browser
Input
Validate JSON against a JSON Schema
Output
4 problems
| Path | Problem |
|---|---|
| /id | Less than minimum 1. |
| Not a valid email. | |
| /roles/1 | Must be one of "admin", "editor", "viewer". |
| /nickname | Property "nickname" is not allowed. |
Implements the validation keywords of draft 2020-12 that real schemas use: type, enum, const, string and number limits, pattern, the common formats, items and prefixItems, required, properties, patternProperties, additionalProperties, allOf, anyOf, oneOf, not, if/then/else and local $ref. Remote references are reported, not fetched.
Runs in this browser. Nothing you paste is sent to a server.
About this tool
Method, assumptions, practical next steps, and limits.
What JSON Schema is for
JSON Schema describes the shape of a JSON document in JSON. OpenAPI 3.1 uses it for request and response bodies, editors use it to autocomplete config files, and services use it to reject bad input before it reaches business logic. The most common bug it catches is additionalProperties: false rejecting a field that a client started sending.
Limits of this validator
Remote $ref URLs are reported rather than fetched, so nothing leaves the page. For production validation use a maintained implementation that passes the official test suite, such as Ajv in JavaScript or opis/json-schema in PHP.
