LLM JSON Schema Validator
Validate that a model actually returned structured output matching the schema you asked for in function calling or JSON mode. Schema errors are reported separately from data errors. Supports draft-07 and 2020-12.
This is useful with OpenAI Structured Outputs: paste the schema from response_format.json_schema.schema or a function tool on the left, and the model JSON on the right.
JSON Schema
Paste or type your content here…
JSON Data (LLM output)
Second input…
Results
Paste a JSON Schema and the model JSON to validate structured output.
Frequently Asked Questions
How do I validate structured output JSON?
Paste the schema you sent the model on the left and the model JSON on the right, then Validate.
Does this work with OpenAI Structured Outputs?
Yes. Paste the JSON Schema from response_format.json_schema.schema or a function definition, then paste the model JSON. OpenAI’s cookbook is https://developers.openai.com/cookbook/examples/structured_outputs_intro
What if my schema itself is broken?
The banner says Your schema has an error, not that the data is invalid.