About
JS

JSON Schema Validator

Validate JSON structure and field rules against a schema

Usage guide and feature details

Why validate data with JSON Schema?

JSON Schema describes types, required fields, enums, lengths and numeric constraints. This tool reports every invalid JSON path and message for API contracts and test data.

JSON Schema Validator is a free online utility for development, testing, and everyday data tasks. It is designed to Validate JSON structure and field rules against a schema. No software installation or account is required.

Practical example and boundaries

Validate an API version field

The validator uses JSON Schema Draft 2020-12 to check types, required fields, ranges, strings, arrays and nested objects, and reports all detectable error paths.

Example input

Data: {"name":"DevKit","version":0}
Schema: {"type":"object","required":["name","version"],"properties":{"version":{"type":"integer","minimum":1}}}

Expected output

$.version must be >= 1

Limitations and cautions

Schema validity does not prove business correctness. Remote $ref documents and custom keywords need additional configuration and are not loaded from unknown locations.

Key features of JSON Schema Validator

  • Process input instantly and spend less time switching between editors, terminals, and third-party apps.
  • Calculations run in your current browser by default, making the tool suitable for code, configuration, and debugging data.
  • Use essential features without registration, sign-in, or routine usage limits.
  • Works on desktop and mobile browsers with clear results that are easy to edit, copy, or download.

How to use JSON Schema Validator

  1. Enter, paste, or select the content in the tool above, then adjust any available options.
  2. Choose the relevant action and JSON Schema Validator will process and validate the input directly in your browser.
  3. Review the output, make any required changes, then copy the result or download the available file.

Common uses for JSON Schema Validator

Use JSON Schema Validator while building front-end pages, debugging APIs, reviewing configuration, preparing test data, or working on technical documentation. It helps you Validate JSON structure and field rules against a schema, which is useful for quick checks, one-off conversions, and repetitive development tasks.

Frequently asked questions about JSON Schema Validator

Which JSON Schema version is supported?

The current AJV 2020 implementation targets Draft 2020-12 with strict mode disabled for common schemas.

Is JSON Schema Validator free to use?

Yes. JSON Schema Validator is free to use without registration and is designed to Validate JSON structure and field rules against a schema.

Is my input uploaded when I use JSON Schema Validator?

This tool runs locally in your browser. Your input is never sent to our servers.