JSON Schema Validator – Validate Against Schema
Validate JSON data against any JSON Schema and get detailed error reports. Our free JSON Schema Validator ensures your data conforms to expected types and structures.
About JSON Schema Validator
JSON Schema defines the expected structure of your data. This validator checks if your JSON matches a schema, verifying types, required fields, and value constraints to catch data issues before they reach production.
How it works
Paste your JSON data and the schema that defines its expected structure. The validator checks types, required properties, string patterns, numeric ranges, and array constraints against your schema.
Each validation error includes the exact path to the problematic field, what was expected, and what was found. This makes fixing data issues straightforward and fast.
When you'd use this
Your API accepts user-submitted JSON and you need to verify it matches your expected format. Validate sample payloads against your schema before implementing server-side validation.
This validator supports common JSON Schema keywords but not the full specification. Complex schemas with advanced features like oneOf or conditional subschemas may not validate correctly.
Questions
What schema keywords are supported?
Type checking, required fields, enum values, string patterns, min/max lengths, numeric ranges, and array item constraints are all supported.
How do I specify required fields?
Add a "required" array to your schema with the names of required properties. Missing required fields generate validation errors.
Can it validate nested objects?
Yes, the validator recursively checks nested objects and arrays. Each nested property is validated against its corresponding schema definition.
What does the path in errors mean?
The path shows the location of the error using dot notation. "$.user.email" means the email field inside the user object has an issue.
Is my data sent anywhere?
No, validation happens entirely in your browser. Your JSON and schema never leave your device, keeping sensitive data secure.