JSON Schema generator

Infer a draft schema from your sample JSON.

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JSON Schema generator processes your input in this browser. Inputs and results are excluded from analytics. Recent tools save tool names, visit counts and last-visit times. Saved tools store only their names. Draft saving is optional and stays on this device; delete saved text with the draft controls. Loading text from a URL is optional and contacts that server; its URL and your IP address are visible to the server. An optional “Use in” action keeps a handoff in this tab. The next tool removes it on arrival and ignores it if more than a minute has passed.

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Sample JSON

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Inferred JSON Schema

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Updated 2026-09-20

JSON Schema generator explained

Generate a JSON Schema draft-07 starting point from one example. Objects become named properties, numbers distinguish integer from fractional values, and mixed arrays use alternative schemas. The generated schema is checked against the original sample before export.

Next: JSON to TypeScript

A worked example

{"name":"Ada","age":30} produces string and integer properties. The required-field option determines whether both fields must be present. It does not infer a minimum age or a list of allowed names.

Next: JSON Schema validator

Before you use the result

A sample cannot establish the complete data contract. Empty arrays leave item types open, additional object properties remain allowed, and string formats, ranges, enums and business rules must be added deliberately. Review the draft against more than one example.

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ToolOctopus. “JSON Schema generator.” Updated 2026-09-20. https://tooloctopus.com/json-schema-generator.

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