JSON to Zod Schema
Generate Zod validation schemas from JSON data instantly. Handles nested objects, arrays, nullable fields, and optional properties. Runs in your browser.
How to Use
- Paste your JSON data into the left panel (or click Example).
- Set the root schema name (used for the exported constant and type).
- Optionally enable strict mode to disallow extra keys.
- Click Generate Zod Schema.
- Click Copy to copy the result into your project.
Output Format
The generator outputs a complete TypeScript snippet including:
import { z } from “zod”— Zod importconst FooSchema = z.object({…})— Schema definitionexport type Foo = z.infer<typeof FooSchema>— Inferred TypeScript type
Common Use Cases
- API validation: Generate schemas from API response examples to validate real responses at runtime.
- Form validation: Convert a form’s expected data shape into Zod schemas for use with react-hook-form or similar.
- Config files: Define and validate configuration objects loaded from JSON files.
- Type safety: Pair with TypeScript to get both runtime validation and static type inference from a single schema.
FAQ
What is Zod?
Zod is a TypeScript-first schema declaration and validation library. It lets you define the shape of your data with a schema, then validate data against that schema at runtime. It's widely used for API response validation, form validation, and configuration parsing.
How does the generator infer types?
The generator inspects each JSON value: strings become z.string(), booleans become z.boolean(), integers become z.number().int(), floats become z.number(), null becomes z.null(), arrays become z.array(), and objects become z.object(). For arrays of objects, keys present in only some items are marked as optional.
What is strict mode?
In strict mode, .strict() is appended to every z.object() call. This causes Zod to reject input objects that contain keys not defined in the schema. Without strict mode, extra keys are silently ignored (the default Zod behavior).
Does this generate production-ready schemas?
The generated schemas are a strong starting point. You should review and refine them — for example, adding .min()/.max() constraints on strings and numbers, converting nullable fields to .nullable().optional(), or splitting nested schemas into separate named constants.
Is my JSON data sent anywhere?
No. All processing happens entirely in your browser. Your JSON data never leaves your device.