generate zod schema from json
Paste the JSON and pick Zod to get the schema and the type inferred with z.infer. Formats such as email, UUID and date-time become specific validators.
The type comes from z.infer.
UUID, email and date-time become their own validators.
Missing in one document and null in another: nullish.
Validators become z.string() methods.
Numeric keys become z.record, not fixed fields.
The item becomes ItemSchema and the array uses z.array.
A field is optional when it is missing from at least one of the objects observed at that position, whether in different documents or in different items of the same array. If every object in a 50-item array has the key phone, it is required; if one does not, it becomes phone?: string. A null value does not make the field optional: it makes it nullable (string | null). The two concepts are different in APIs and in languages, so the tool keeps them apart. The All fields optional switch marks every field optional, which is useful for PATCH bodies and partial responses.
.optional() accepts undefined, meaning an absent key. .nullable() accepts null. .nullish() accepts both. In JSON, absent and null are different things, and the tool uses each method according to what the samples show.
The default output targets version 4. Choose Zod 3 under Options if your project still uses it: the format validators become z.string() methods and z.record takes only the value schema.
Not by default: Zod z.object strips unknown keys when validating instead of failing. To reject them, use z.strictObject() in version 4 or .strict() in 3. The generator does not add it because samples rarely show every key the API may send.
Yes. Pick TypeScript instead of Zod to get just the interface. Zod pays off when data comes from outside, such as API responses, forms and files.
export type Root = RootItem[];
export interface RootItem {
id: number;
number: string;
status: string;
createdAt: string;
total: number;
customer: Customer;
items: Item[];
tags: string[];
shipping: Shipping;
billing?: Shipping;
couponCode?: string;
}
export interface Customer {
id: string;
name: string;
email: string;
phone: string | null;
}
export interface Item {
sku: string;
name: string;
qty: number;
price: number;
}
export interface Shipping {
street: string;
city: string;
zip: string;
}
A string with a few repeated values, in at least 8 samples, becomes an enum.
Date-time, date, UUID, email, URL and IPv4.
Objects with the same fields become one type.
Keys that look like ids or dates become a map, and an empty object becomes a map of unknown values.
A fixed-length array with different types per position, like ["a", 1].
Avoids int when the samples happen to contain only integers.
Rejects trailing commas, comments, single quotes and similar.
Language style: camelCase, snake_case or PascalCase, annotated with the original key. Dataclass and TypedDict always keep the keys.
Go, C#, Java, Swift and Pydantic. In other languages the field stays a string.
readonly in TypeScript, frozen in Python, init in C# classes and let in Swift.
The JSON is processed in your browser. Nothing you paste or open is sent to servers.