TypeScript to JSON Schema

Paste a TypeScript interface or type and get a JSON Schema (Draft 2020-12) document back. Runs entirely in your browser — your TypeScript is never uploaded.

TypeScript Input

JSON Schema Output

Use $defs for referenced types additionalProperties: false

What this converter handles

• interface and top-level type aliases
• Primitives: string, number, boolean, null
• Optional properties become absent from required
• Unions become anyOf
• String/number literal unions become enum
• Arrays T[] become { type: "array", items: T }
• Record<string, V> becomes additionalProperties
• References to other declared interfaces resolve via $ref

Why JSON Schema?

JSON Schema is the standard for describing JSON document shapes — it's what API gateways, message queues, configuration validators, and AJV use under the hood. Generating schemas from your TypeScript types means you only maintain the type definitions; the runtime guards stay in sync automatically.

For drop-in Zod schemas instead, see the TypeScript → Zod converter.

Related tools

JSON Schema to TypeScript ›

Go the other direction — turn a schema into a TS interface.

TypeScript to Zod ›

Generate Zod schemas instead of JSON Schema.

JSON to TypeScript ›

From a JSON sample to a TS interface.