JSON Schema Validator
Validate JSON data against a JSON Schema Draft 2020-12 document in your browser.
Try a small example
Try a small example
Load the fictional example in a cleared form. Check the options, run the tool if needed, and compare the result below.
Check a JSON document against a JSON Schema Draft 2020-12 schema. Syntax errors are separate from schema violations, and each violation includes its JSON instance path. Paste the JSON data and JSON Schema Draft 2020-12 document, then validate. Syntax errors are separate from schema issues, which show the data path and rule. format values are not asserted and remote references are never loaded; keep reusable definitions in local $defs. JSON Schema format keywords are annotations here and are not checked. Remote references are not fetched; local references within the pasted schema can be used. Data and schema are limited to 1,000,000 characters each, and the report shows at most 100 issues.
JSON data to validate
{"name":"Ada","count":2}JSON Schema (2020-12)
{"type":"object","properties":{"name":{"type":"string"},"count":{"type":"integer","minimum":0}},"required":["name","count"],"additionalProperties":false}Expected output
Valid: the JSON data matches the schema.
The example is unavailable until the tool is ready.
Text is processed in your browser.
Share this tool
Only the tool’s public link is shared. Your inputs and results stay here.
Show link to copy manually
Quick answer
Check a JSON document against a JSON Schema Draft 2020-12 schema. Syntax errors are separate from schema violations, and each violation includes its JSON instance path.
The page and its assets load from the site; this operation uses your entered values only in this browser and does not send them to a calculation endpoint.
How to use it
Paste the JSON data and JSON Schema Draft 2020-12 document, then validate. Syntax errors are separate from schema issues, which show the data path and rule. format values are not asserted and remote references are never loaded; keep reusable definitions in local $defs.
Limits
JSON Schema format keywords are annotations here and are not checked. Remote references are not fetched; local references within the pasted schema can be used. Data and schema are limited to 1,000,000 characters each, and the report shows at most 100 issues.
Frequently asked questions
Which JSON Schema draft is supported?
Draft 2020-12. The schema is checked for validity before the data is tested. Unknown keywords are ignored according to the standard; unsupported schema declarations and invalid schemas are reported. Check keyword spelling and do not assume a custom extension was validated.
Are format values validated?
No. format is treated as an annotation in this tool. A value such as an email address or date may therefore pass without format-specific checking.
Does the tool fetch $ref URLs?
No. No remote schema is loaded. Keep referenced definitions inside the pasted schema, for example in $defs.
Are my inputs sent to a server?
Validation runs in this browser after the page loads; the entered data and schema are not sent to a validation service.
Are unknown schema keywords validated?
No. Unknown keywords are ignored according to JSON Schema semantics. Check keyword spelling carefully. Standard schemas such as required properties without a properties definition are accepted; format remains an annotation and remote references are not fetched.
Sources and references
These references document the cited standard or browser API; they do not validate the tool’s output.