JSON Schema Validator

What is Schema Validator?

The JSON Schema Validator takes a document and a schema and reports every violation with a clear JSON Pointer path and a human-readable explanation — so you can fix data before deploying, or validate incoming API payloads against a contract.

How it works

We parse both the document and the schema with our hand-rolled tokenizer, then compile the schema with Ajv (the standard JSON Schema validation library) and run the document through it. Every validation error is listed with its JSON Pointer path and the exact rule that failed.

1. Paste the JSON document. Drop or paste the JSON document you want to validate — for example, an API request body.
2. Paste the schema. Paste a valid JSON Schema document. Tool auto-detects the draft version from the $schema field, or you can pick one manually.
3. Read the results. A valid/invalid badge and a full error list with JSON Pointer paths for every violation.

Examples

Name must be a string

A document with name: 42 against a schema requiring type "string" reports "/name: must be string".

Required field missing

A document missing an email field reports "/email: must have required property 'email'".

Common mistakes

Invalid schema JSON

The schema itself must be valid JSON. If it contains trailing commas or unquoted keys, fix those first.

Draft version mismatch

Make sure the $schema field in your schema matches the draft version you intend. If absent, we default to the chosen draft.

Alternatives

JSON Schema Generator

If you don't have a schema yet, generate one from sample data.

JSON Validator

For syntax-only validation (no schema), use the lighter JSON Validator.

Frequently asked questions