How to use the JSON to Zod Schema
Generate Zod schemas instantly:
1
Paste your JSON
Paste a JSON object representing the shape you want to validate. Arrays of objects are also accepted — the first element is used for inference.
2
Set the schema name
Enter a name for the exported Zod schema (e.g. UserSchema, ProductSchema). It's automatically converted to PascalCase.
3
Click Generate
Get a complete Zod schema with z.object(), z.string().email(), z.string().url(), z.number().int(), z.array(), and fully nested schemas.
4
Copy into your project
Paste into your TypeScript file. Use schema.parse() or schema.safeParse() to validate data at runtime. A z.infer<> type is included automatically.
When to use this tool
Generate Zod schemas from JSON instead of writing them by hand:
- →Validating API responses with Zod in your TypeScript or Next.js project
- →Generating runtime type validators from JSON API documentation
- →Adding input validation to tRPC procedures from existing request shapes
- →Converting JSON fixtures into Zod schemas for test factories
- →Scaffolding React Hook Form validators from existing API response shapes
Frequently asked questions
Q:How are JSON types mapped to Zod validators?
Strings become z.string(), integers become z.number().int(), floats become z.number(), booleans become z.boolean(), null becomes z.string().nullable(), arrays become z.array(), and nested objects become z.object(). Email, URL, UUID, and ISO datetime strings get additional refinements like z.string().email() and z.string().datetime() based on field name and value patterns.
Q:How are null values handled in Zod schemas?
Null values generate z.string().nullable(). If a field can be either a value or absent entirely, add .optional() after generation — for example z.string().nullable().optional(). The generator flags nullable fields in the info banner as a reminder.
Q:Does it generate .optional() fields?
Not automatically — optional fields require knowledge of which keys may be absent from real payloads, which can't be inferred from a single sample. After generating, add .optional() to any fields that may be missing in actual API responses.
Q:Can I use the output with React Hook Form?
Yes — Zod schemas integrate directly with React Hook Form via the @hookform/resolvers/zod package. Pass the generated schema to zodResolver() and use the exported z.infer<> type as your form's type.
Q:Does it work with tRPC?
Yes — tRPC uses Zod natively for input validation. Paste the generated schema directly as the input validator for your tRPC procedures using .input(YourSchema).