Paste your TypeScript interfaces, types, or enums and get production-ready Zod validation schemas. Handles optional fields, union types, arrays, nested objects, and enums.

How It Works

The converter parses your TypeScript source using pattern matching to extract interfaces, type aliases, and enum declarations. Each field type is mapped to its Zod equivalent: string becomes z.string(), optional fields (?:) get .optional(), union types become z.union(), and literal types become z.literal(). Nested objects and arrays are handled recursively.

The output includes both the Zod schema and a re-exported type via z.infer, so you can replace your original interface with the schema as the single source of truth. All processing runs client-side.

TypeScript to Zod Mapping

TypeScript	Zod Schema	Notes
`string`	`z.string()`	Basic string validation
`number`	`z.number()`	Integers and floats
`boolean`	`z.boolean()`	true or false
`field?: type`	`z.type().optional()`	Field may be absent
`type \| null`	`z.type().nullable()`	Field may be null
`string[]`	`z.array(z.string())`	Typed array
`Array<T>`	`z.array(TSchema)`	Generic array syntax
`"a" \| "b" \| "c"`	`z.union([z.literal("a"), ...])`	String literal union
`{ nested: string }`	`z.object({ nested: z.string() })`	Inline object types
`Record<string, T>`	`z.record(z.string(), TSchema)`	Dynamic keys
`enum Status { ... }`	`z.enum([...])`	String enum values
`any`	`z.any()`	No validation
`unknown`	`z.unknown()`	Requires narrowing

When to Use Zod Over Plain TypeScript

TypeScript types disappear at runtime. That means your API response types, form data shapes, and environment variables have zero protection once code is compiled. Zod bridges this gap by giving you schemas that validate data at runtime while also producing static types. Here are the concrete scenarios where Zod adds value over plain TypeScript:

API boundaries — validate incoming request bodies and outgoing responses in Express, Fastify, or Next.js API routes
Form validation — pair with React Hook Form via @hookform/resolvers/zod for type-safe form handling
Environment variables — validate process.env at startup to catch missing config early
Third-party data — validate webhook payloads, database query results, and external API responses
tRPC procedures — Zod schemas are the standard input validators in tRPC

FAQ

Does this use the TypeScript compiler?

No. The tool uses regex-based pattern matching rather than the full TypeScript compiler API. This makes it fast and lightweight (runs instantly in your browser) but means deeply complex types like conditional types (T extends U ? X : Y) or mapped types (Partial<T>) are not converted. For those cases, write the Zod schema manually and infer the type from it.

How does it handle references between interfaces?

When a field references another interface (like author: User), the converter generates author: UserSchema. Both schemas are included in the output as long as both interfaces are in your input. Make sure to paste all related types together for complete output.

Can I use the output in production code?

Yes. The generated schemas use standard Zod API calls and include the import statement. Copy the output into your project, install Zod (npm install zod), and the schemas are ready to use. You may want to add custom refinements (like .email() for email fields or .min(1) for required strings) that cannot be inferred from type annotations.

What is the difference between this tool and JSON to Zod?

The JSON to Zod converter infers a schema from actual data values (a JSON object), while this tool converts TypeScript type definitions directly. Use JSON to Zod when you have example data; use TypeScript to Zod when you have existing interfaces you want to add runtime validation to.

Start from JSON instead? JSON to Zod converter or JSON to TypeScript interfaces.

TypeScript to Zod Schema Converter