JSON to Zod Schema Converter
Paste a JSON sample to instantly generate a matching Zod schema for runtime validation in TypeScript or JavaScript. Free online developer tool.
Paste JSON
Zod Schema
Zod schema definitions will appear here...
Free JSON to Zod Schema Converter
Paste a JSON sample to instantly generate a matching Zod schema you can use to validate data at runtime in a TypeScript or JavaScript project.
How to Use It
Paste any JSON object or array, or click "Load Example." The tool infers a type shape and emits a z.object({...}) schema for every object level, pulling nested objects out into their own named schema constant, wrapping arrays in z.array(...), and chaining.nullable() and/or .optional() onto any field that was ever nullor missing from a sample.
Example
Given {"name": "Ann", "age": 30, "tags": ["a","b"], "address": {"city": "NYC", "zip": null}}, the tool emits const RootAddressSchema = z.object({ city: z.string(), zip: z.null() });and a RootSchema that references it, with tags: z.array(z.string()).
Common Use Cases
- Validating API responses or form submissions at runtime with Zod.
- Generating a starting schema for a tRPC or Next.js Server Action input type.
- Deriving a static TypeScript type from the schema with Zod's
z.infer<typeof Schema>.
FAQs
Why are nested schemas defined before the root schema?
JavaScript evaluates const declarations top to bottom, and the root schema references its nested schemas by name — so those need to be defined earlier in the file, or you'd get a "used before it was defined" error at runtime.
Does the generated code include a Zod import?
No — only the schema declarations are generated. Add import { z } from "zod";at the top of the file where you paste the output.
Is my JSON uploaded anywhere?
No — parsing and schema generation happen entirely client-side in your browser. Nothing you paste is sent to a server.