JSON Schema Validator
Validate JSON data against a JSON Schema in your browser — checks type, required, properties, items, enum and min/max, with error paths.
About the JSON Schema Validator
This JSON Schema validator checks a JSON document against a schema and lists every violation with the exact path where it occurred. It implements the core draft-07 keywords developers use most: type, required, properties, additionalProperties, items, enum, const, minimum/maximum, minLength/maxLength, pattern and minItems/maxItems.
Instead of a vague pass/fail, you get actionable errors like 'user.age: expected integer, got string' or 'items[2]: missing required property price', so you can fix data or tighten a schema quickly.
Both the data and the schema are processed entirely in your browser — nothing is uploaded — making it safe for real payloads and private schemas.
How to Use the JSON Schema Validator
- 1Paste your JSON data in one box and your JSON Schema in the other.
- 2Click Validate to check the data against the schema.
- 3Review the pass result or the list of errors with their paths.
- 4Fix the data or the schema and re-validate.
Frequently Asked Questions
Which JSON Schema keywords are supported?
The core draft-07 set: type, required, properties, additionalProperties, items, enum, const, minimum, maximum, exclusiveMinimum/Maximum, minLength, maxLength, pattern, minItems and maxItems. This covers the vast majority of real-world schemas. Advanced features like $ref, allOf/anyOf/oneOf and remote references are not evaluated.
How are validation errors reported?
Each error names the JSON path where it occurred and what failed — for example 'address.zip: does not match pattern' or 'tags: expected array'. Paths use dot and bracket notation so you can locate the offending value immediately in nested structures.
What's the difference between this and a schema generator?
A generator creates a schema from sample data; a validator checks data against an existing schema. Use the generator to draft a schema, refine it, then use this validator to enforce it against incoming documents.
Does it support draft 2020-12 features?
It targets the widely-used draft-07 core keywords. Newer drafts add features like prefixItems and dynamic references that aren't evaluated here. For most validation tasks the draft-07 keywords are sufficient; for full spec coverage use a library like Ajv in your build.
Is my data or schema uploaded?
No. Validation runs entirely in your browser, so neither the data nor the schema is transmitted or stored. It's safe for confidential payloads and proprietary schemas.