Convert JSON Arrays of Objects to Zod Array Schemas

Typing Arrays with Zod

When JSON contains an array of objects, the converter inspects every element to determine a unified schema for the array items, then wraps it in z.array().

Example JSON

{
  "users": [
    { "id": 1, "name": "Alice", "role": "admin" },
    { "id": 2, "name": "Bob", "role": "editor" },
    { "id": 3, "name": "Carol", "role": "viewer" }
  ]
}

Generated Zod Schema

import { z } from "zod";

const usersItemSchema = z.object({
  id: z.number().int(),
  name: z.string(),
  role: z.string(),
});

const rootSchema = z.object({
  users: z.array(usersItemSchema),
});

type UsersItem = z.infer<typeof usersItemSchema>;
type Root = z.infer<typeof rootSchema>;

Array Validation Methods

Zod arrays support powerful validation chains:

// Minimum and maximum length
z.array(usersItemSchema).min(1).max(100)

// Non-empty array
z.array(usersItemSchema).nonempty()

// Exact length
z.array(usersItemSchema).length(3)

Primitive Arrays

Arrays of primitives map directly:

JSON	Zod schema
[1, 2, 3]	z.array(z.number())
["a", "b"]	z.array(z.string())
[true, false]	z.array(z.boolean())
[1, "two", true]	z.array(z.union([z.number(), z.string(), z.boolean()]))

Mixed-Type Arrays

When an array contains elements of different types, Zod uses z.union() to accept any of them:

const mixedSchema = z.array(
  z.union([z.string(), z.number(), z.boolean()])
);

This validates that every element is one of the specified types, providing both flexibility and safety.