Developer ToolsCode ValidatorsFree Tool
JSON Schema Validator
Validate JSON data against a simplified schema — checks required fields are present and basic property types match.
How to Use JSON Schema Validator
- 1Paste your JSON Schema
- 2Add a line with ---
- 3Paste the JSON data to validate
- 4Click Process to see required-field and type-mismatch errors
Frequently Asked Questions
Two things: whether every field listed in the schema's 'required' array is present in your data, and whether each property in 'properties' matches its declared 'type'. That's it.
No — it's a simplified subset. Features like patterns, enums, min/max constraints, nested object/array schemas, $ref references, and format validators are not checked.
Your JSON Schema, then a line with just ---, then the JSON data to validate against it.
No — validation runs entirely in your browser.
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