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JSON to Types

Infer type definitions from JSON for TypeScript, Go, Java and Kotlin — auto-names nested types, merges object shapes across array items, and marks nullable fields.

Target

Root nameNull values → optional / nullable

JSON input

344 chars · 17 lines

TypeScript interfaces

interface Root2 {
    id: number;
    name: string;
    active: boolean;
    score: number;
    middleName?: null | null;
    address: Root2Address;
    roles: string[];
    posts: Root2Post[];
}

interface Root2Address {
    city: string;
    zip: string;
    geo: Root2AddressGeo;
}

interface Root2AddressGeo {
    lat: number;
    lng: number;
}

interface Root2Post {
    title: string;
    views: number;
    pinned?: boolean | null;
}

441 chars · 27 lines