JSON Schema validator

How it works

JSON Schema describes the shape a JSON document must have: which fields are required, what type each one is, which values are allowed and which format they follow. OpenAPI, API validation, config files and many editors use it. This validator tells you whether a document matches a schema and, if not, why.

Paste the schema on the left and the document on the right. Validation runs as you type. If either one is not valid JSON, you get the line and column of the error.

Each problem shows its path in the document, like /items/0/email, the failing rule (required, type, enum, minimum, format, additionalProperties…) and the detail. All errors are listed, not just the first, and messages that only summarize others are left out so the list stays clear.

The draft is detected from $schema and you can override it: 4, 7, 2019-09 or 2020-12. It is handy for testing a schema before publishing it, debugging why an API rejects a payload or reviewing a service configuration.

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Examples

Schema: integer id ≥ 1, email with format, plan in [free, pro, team], no extra properties
Document: {"id": 0, "email": "ana.ejemplo.dev", "plan": "enterprise", "activo": true}

/id      minimum               0 is less than 1.
/email   format                String does not match format "email".
/plan    enum                  Instance does not match any of ["free","pro","team"].
(root)   additionalProperties  Property "activo" does not match additional properties schema.

{"id": 42, "email": "ana@ejemplo.dev", "plan": "pro"}

The document matches the schema

Frequently asked questions