JSON to Zod Schema

Zod is a TypeScript-first schema declaration and validation library. You define a schema once using Zod's fluent API, and it serves two purposes: runtime validation (catching invalid data from API responses or user input before it reaches your code) and static TypeScript type inference (generating z.infer<typeof schema> to get the TypeScript type automatically).

Instead of writing both a TypeScript interface and a runtime validator separately, Zod lets you write the schema once and derive the type from it. This is especially valuable for validating API responses, form inputs, environment variables, and configuration objects. This tool generates a Zod schema from any JSON so you can add runtime validation to existing code instantly.

Input JSON:

{
  "id": 1,
  "name": "Ravi Kumar",
  "active": true,
  "address": { "city": "Surat", "country": "IN" }
}

Generated Zod schema:

import { z } from "zod";

export const schema = z.object({
  id: z.number().int(),
  name: z.string(),
  active: z.boolean(),
  address: z.object({
    city: z.string(),
    country: z.string()
  })
});

export type Schema = z.infer<typeof schema>;

• ▸API response validation — Paste your API response JSON and get a Zod schema to validate all future responses at runtime.
• ▸Form validation — Generate a Zod schema from your form's default value object for use with react-hook-form.
• ▸Environment variable schemas — Validate process.env values against a Zod schema generated from your config shape.
• ▸tRPC / Next.js API routes — Generate input validators for tRPC procedures and Next.js API route handlers.

import { schema, type Schema } from "./schema";

// Validate API response
const data: Schema = schema.parse(await res.json());

// Safe parse (no throw)
const result = schema.safeParse(response);
if (!result.success) {
  console.error(result.error.issues);
}