Which OpenAPI versions are supported?

This converter supports OpenAPI 3.0.x and 3.1.x specifications, as well as Swagger 2.0 JSON format. It handles components/schemas, nested objects, arrays, and discriminated unions.

Is my API specification sent to a server?

No. All parsing and Zod schema generation happens 100% client-side in your browser. Your API specs never leave your device.

Does it handle nested objects and allOf/oneOf?

Yes. The converter resolves allOf (intersection), oneOf (discriminated unions), and anyOf compositions. It produces clean z.object(), z.union(), and z.intersection() calls.

Can I use the output in production?

Yes. The generated Zod schemas are production-ready TypeScript code that imports directly from the zod package. Use them for API response validation, form inputs, or type-safe data pipelines.

OpenAPI → Zod Converter

Transform third-party API specs into runtime type safety. Parse OpenAPI 3.x JSON directly into production-ready Zod schemas with full validation support.

OpenAPI JSON

1.2KB

{
  "openapi": "3.1.0",
  "info": { "title": "Sample API", "version": "1.0.0" },
  "components": {
    "schemas": {
      "User": {
        "type": "object",
        "required": ["id", "email", "role"],
        "properties": {
          "id": { "type": "string", "format": "uuid" },
          "email": { "type": "string", "format": "email" },
          "name": { "type": "string", "minLength": 1, "maxLength": 100 },
          "age": { "type": "integer", "minimum": 18, "maximum": 120 },
          "role": { "type": "string", "enum": ["ADMIN", "USER", "GUEST"] },
          "tags": { "type": "array", "items": { "type": "string" } },
          "metadata": { "type": "object", "additionalProperties": true }
        }
      },
      "Post": {
        "type": "object",
        "required": ["id", "title", "author"],
        "properties": {
          "id": { "type": "string", "format": "uuid" },
          "title": { "type": "string", "minLength": 1 },
          "content": { "type": "string", "nullable": true },
          "author": { "$ref": "#/components/schemas/User" },
          "publishedAt": { "type": "string", "format": "date-time" }
        }
      }
    }
  }
}

Zod Schema Output

import { z } from "zod";

// Generated from OpenAPI 3.1.0
// Sample API v1.0.0

export const UserSchema = z.object({
  id: z.string().uuid(),
  email: z.string().email(),
  name: z.string().min(1).max(100).optional(),
  age: z.number().int().min(18).max(120).optional(),
  role: z.enum(["ADMIN", "USER", "GUEST"]),
  tags: z.array(z.string()).optional(),
  metadata: z.object({}).passthrough().optional(),
}).strict();
export type User = z.infer<typeof UserSchema>;

export const PostSchema = z.object({
  id: z.string().uuid(),
  title: z.string().min(1),
  content: z.string().nullable().optional().nullable(),
  author: z.object({
    id: z.string().uuid(),
    email: z.string().email(),
    name: z.string().min(1).max(100).optional(),
    age: z.number().int().min(18).max(120).optional(),
    role: z.enum(["ADMIN", "USER", "GUEST"]),
    tags: z.array(z.string()).optional(),
    metadata: z.object({}).passthrough().optional(),
  }).strict(),
  publishedAt: z.string().datetime().optional(),
}).strict();
export type Post = z.infer<typeof PostSchema>;

// Successfully converted 2 schemas

Why Runtime Validation Matters

From Static Types to Runtime Safety

TypeScript interfaces provide compile-time guarantees, but they vanish at runtime. When consuming external APIs, a single schema change can crash your production app. Zod schemas bridge this gap by validating actual payloads against expected structures, catching breaking changes before they reach your users.

How This Tool Works

This converter parses the components.schemas block of OpenAPI 3.x documents and recursively maps properties, arrays, enums, discriminated unions, and format constraints (emails, UUIDs, datetimes) into production-ready Zod definitions. All processing happens locally—your proprietary API specs remain 100% private.