DevBolt

JSON Schema Draft-07 Validator

Validate your JSON data against a Draft-07 schema and get clear, actionable error messages. Everything runs client-side — no data is transmitted to any server.

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JSON Schema Validator

Validate JSON data against a JSON Schema (Draft 07) with detailed error reporting. Generate schemas from sample data or load examples to get started.

Load example:
JSON Schema Quick Reference

JSON Schema is a vocabulary for annotating and validating JSON documents. It describes the structure, constraints, and documentation of JSON data.

Common keywords:
  • type — Data type: string, number, integer, boolean, object, array, null
  • required — Array of required property names
  • properties — Object property schemas
  • items — Schema for array elements
  • enum — Allowed values
  • pattern — Regex pattern for strings
  • minimum / maximum — Number range constraints
  • minLength / maxLength — String length constraints
  • format — Semantic format: email, uri, date-time, ipv4, uuid, etc.
  • additionalProperties — Allow or deny extra properties on objects
Combining schemas:
  • allOf — Must match all schemas
  • anyOf — Must match at least one schema
  • oneOf — Must match exactly one schema
  • not — Must not match the schema

This tool supports JSON Schema Draft 07 with format validation (email, URI, date-time, etc.) via ajv-formats. Everything runs in your browser — no data is sent over the network.

What is JSON Schema Draft-07?

Draft-07 (published 2018) is the most widely adopted version of the JSON Schema specification. It introduced conditional keywords like if/then/else, the readOnly and writeOnly annotations, and the contentMediaType/contentEncoding keywords. Most major validation libraries — including Ajv, jsonschema (Python), and everit-json-schema (Java) — fully support Draft-07.

Common use cases

Draft-07 validation is used in CI/CD pipelines to validate configuration files, in API gateways to reject malformed requests, in form builders to enforce input rules, and in data engineering to validate records before loading into warehouses. Catching schema violations early prevents runtime errors and data corruption downstream.

Frequently Asked Questions

Should I use Draft-07 or a newer draft?

Draft-07 has the broadest library and tooling support. Newer drafts (2019-09, 2020-12) add features like $dynamicRef and prefixItems, but many tools have not fully adopted them yet. Draft-07 is a safe, well-supported choice for most projects.

What errors does the validator report?

The validator reports type mismatches, missing required properties, pattern violations, array length issues, enum mismatches, and conditional failures. Each error includes the JSON path to the problematic value and a human-readable message.