JSON Schema Generator
Generate a Draft 2020-12 JSON Schema from sample JSON directly in your browser.
Your data is processed locally in your browser and is never uploaded.
How schema inference works
JSONPlease maps JSON values to schema types and merges arrays of objects. Fields seen in every object sample are required; other fields are optional.
Predictable output
The generator does not guess formats, enums, ranges, descriptions, or whether additional properties are forbidden. Generated schemas are inferred from sample data and may need manual refinement for production validation.
Private local generation
Your JSON is processed locally in your browser and is never uploaded.