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JSON Schema Generator from Sample

Paste a sample JSON document and get a draft-07 JSON Schema — types, string formats, nesting, and required fields inferred automatically. Everything runs in your browser.

Schema appears here.
Array item types are inferred from the first element only — if your arrays mix types, adjust the schema by hand.

About this tool

The generator walks your sample recursively and emits a draft-07 JSON Schema: whole numbers become integer, decimals become number, and strings that look like emails, URLs, or ISO 8601 timestamps get format: "email", "uri", or "date-time" annotations. Nested objects and arrays are handled to any depth. By default every key present in the sample is listed as required — toggle that off if some fields are optional. One honest limitation: array item schemas come from the first element only, so heterogeneous arrays need manual editing.

Your JSON never leaves the page — there is no server, no upload, and no tracking of tool inputs.

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Found this useful? 113 free, browser-only tools by Yuvrajsinh Jadav — an engineer who ships production AI systems. No account, nothing sent anywhere.
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