Validate JSON against a JSON Schema

How it works

1. 1

   Paste the JSON document.

2. 2

   Paste the JSON Schema.

3. 3

   Read the result and any listed errors.

4. 4

   Fix the document or schema and check again.

About the JSON Schema Validator

A JSON Schema describes what a valid document looks like: required fields, types, allowed values and formats. Checking real data against it catches broken API payloads and config files before they reach production. This validator checks a JSON document against your schema in the browser and lists every failure with a JSON Pointer path, so you can see exactly which field broke which rule.

What you can do

• Validate as you type and see either a valid confirmation or a numbered list of errors.
• Find each problem by its path, such as /items/2/price, with a plain message like must be >= 0.
• Use type, enum, const, number limits, string length and pattern, array rules and object rules such as required and additionalProperties.
• Combine schemas with allOf, anyOf, oneOf, not and if, then, else.
• Reuse definitions with local $ref pointers, with draft-04 to draft-07 $ref behaviour when the $schema says so.

When it works best

• Checking a webhook or API payload against the schema in your OpenAPI documentation.
• Testing a schema you are writing against good and bad example documents.
• Finding which field in a large config file fails a CI validation step.

Things to know

• Both documents stay in your browser.
• Only local $ref values starting with # are resolved; references to other files or URLs are rejected.
• The format keyword, such as email or date-time, is not checked, and some newer keywords like unevaluatedProperties and dependentRequired are ignored.
• For syntax errors alone, the JSON Formatter is quicker. To create types from a sample, use JSON to TypeScript/PHP.

Frequently asked questions