How it works
- 1
Paste your JSON
Drop in any JSON — an API response, webhook payload, database record, or config file. Or pick one of the quick-start examples.
- 2
Pick your output format
Switch between TypeScript, Zod, JSON Schema Draft 7, OpenAPI 3.0, Yup, and Valibot tabs. All six are generated simultaneously from the same JSON.
- 3
Copy and paste into your project
Each tab has a one-click copy button. Paste the schema directly into your codebase — no cleanup needed.
Quick examples
export interface Profile {
displayName: string;
avatarUrl: string;
bio: null | null;
}
export interface Root {
id: number;
username: string;
email: string;
role: string;
active: boolean;
createdAt: string;
profile: Profile;
tags: string[];
}🛡️ Verify zero uploads — open DevTools → Network tab
Open your browser's DevTools (F12), go to the Network tab, and use this tool. You will see zero outbound requests — all processing runs inside your browser sandbox via WebAssembly or pure JavaScript. Nothing you paste or upload is ever sent anywhere.
Use cases
Document an API quickly
Paste a real API response to get an OpenAPI 3.0 schema component — the foundation of an `openapi.yaml` spec — in under 10 seconds.
Bootstrap runtime validation
Generate a Zod or Yup schema from a real payload to add input validation to an existing endpoint without hand-writing every field.
Share schemas across teams
JSON Schema is language-agnostic — generate it once and share with backend, frontend, and mobile teams who all use different validation libraries.
Frequently Asked Questions
How is this different from json-to-typescript?
The /json-to-typescript tool generates TypeScript, Zod, and Valibot. The Schema Toolkit adds JSON Schema Draft 7, OpenAPI 3.0 components, and Yup — giving you six output formats in one place.
Does the OpenAPI output include path definitions?
The OpenAPI output focuses on the `components.schemas` section — the inferred types from your JSON. It includes a minimal top-level OpenAPI 3.0 envelope (`openapi`, `info`, `paths: {}`) so the document is valid, but adding actual API paths is left to you.
Which JSON Schema draft does this use?
JSON Schema Draft 7 (`$schema: http://json-schema.org/draft-07/schema#`). Draft 7 is the most widely supported and is compatible with AJV, jsonschema (Python), and most JSON Schema validators.
Can I use the Yup output with React Hook Form?
Yes. The generated Yup schemas work with `@hookform/resolvers/yup`. The schemas use `.object({...}).required()` which is the standard React Hook Form integration pattern.
Does anything leave the browser?
No. All parsing and code generation runs entirely in your browser. Your JSON never leaves the tab — there are no server calls. Open DevTools → Network while using the tool to verify.
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