JSON Schema Validator
Paste a JSON value and a draft-07 JSON Schema to validate one against the other instantly. It checks types, required keys, ranges, patterns, formats and anyOf/allOf/oneOf/not, then lists every failure with the exact path so you can fix data fast.
How to validate JSON against a schema
- Paste the JSON value you want to check into the instance editor.
- Paste your draft-07 JSON Schema into the schema editor.
- Read the valid or invalid result and the list of errors, each with its path.
Examples
Valid object against a person schema
instance: {"name":"Ada","age":36}
schema: {"type":"object","required":["name"],"properties":{"name":{"type":"string"},"age":{"type":"integer","minimum":0}}}Valid. No errors.
Missing required key and value below minimum
instance: {"age":-1}
schema: {"type":"object","required":["name"],"properties":{"name":{"type":"string"},"age":{"type":"integer","minimum":0}}}/name: Missing required property "name" /age: Value -1 is below minimum 0
Frequently asked questions
Which JSON Schema draft does this support?
It validates against a practical subset of draft-07. Supported keywords include type, required, properties, additionalProperties, items, enum, const, minimum, maximum, exclusiveMinimum, exclusiveMaximum, multipleOf, minLength, maxLength, pattern, minItems, maxItems, uniqueItems, minProperties, maxProperties, format, and the combinators anyOf, allOf, oneOf and not.
What does the path in each error mean?
Each error carries a JSON-pointer-ish path to the part of your data that failed, such as /age or /user/id. The empty path refers to the root value. This points you straight at the field to fix.
Does it stop at the first error or show them all?
It collects every error in one pass, so you can see all problems at once instead of fixing one, revalidating, and finding the next.
Which formats are checked?
Basic checks for email, uri, date and uuid. These are pragmatic patterns, not full RFC validators, so treat them as a quick sanity check rather than strict conformance.
Is my JSON sent to a server?
No. Validation runs entirely in your browser, so neither your data nor your schema ever leaves your machine.
What is not supported?
This is a focused subset, so $ref and remote references, definitions, dependencies, if/then/else, patternProperties and tuple-specific keywords like additionalItems are not evaluated. Unknown keywords are ignored rather than rejected.
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