free_tool
JSON to TypeScript & Zod
Paste a JSON response, get TypeScript interfaces and a matching Zod schema you can drop straight into your codebase. Nested objects become named types, arrays of objects merge into one shape with optional fields, and mixed types become unions. It runs entirely in your browser, so nothing you paste leaves the page.
export interface Profile {
city: string;
verifiedAt: null;
}
export interface Post {
id: number;
title: string;
pinned?: boolean;
}
export interface Root {
id: number;
name: string;
active: boolean;
roles: string[];
profile: Profile;
posts: Post[];
}Turning a sprawling API response into types by hand? I build typed, validated API layers so bad data fails at the edge, not three functions deep.
Type your API end to end: book a callInference is structural: it describes the sample you give it. A field that is null in the sample types as null, and a key missing from some array elements becomes optional, so feed it a representative payload (ideally a few records) for the best result. Generated Zod imports from "zod".
why_both
Types describe; Zod enforces
A TypeScript interface is a promise the compiler trusts. At runtime that promise is worthless: the API can send a string where you typed a number, and TypeScript never finds out. Zod closes the gap by validating the actual payload, so bad data fails loudly at the boundary instead of corrupting state three functions deep.
Generating both from the same sample keeps them in lockstep. Parse with the Zod schema at the edge (the fetch, the webhook, the form), and infer the TypeScript type from it with z.infer so you never write the shape twice.
Want your data typed and validated end to end?
I build typed API layers with validation at the boundary, so a bad response fails fast and visibly instead of leaking through your app. Book a call, or leave your email.