What is JSON to Valibot Schema Generator?
Valibot is a lightweight and modular TypeScript schema validation library that validates data at runtime while inferring TypeScript types automatically. It uses a functional API with namespace imports (import * as v from 'valibot') and provides tree-shakeable validators. This tool converts your JSON data into Valibot v1 schemas automatically, handling type inference, nested objects, email and URL detection, and nullable field handling.
How to Use
- Set the root schema name in the options bar
- Choose how null values should be handled: v.union([... , v.null()]), v.nullable(...), or v.optional(...)
- Toggle "Detect email" to automatically use v.pipe(v.string(), v.email()) for email-like fields
- Toggle "Detect URL" to automatically use v.pipe(v.string(), v.url()) for URL-like fields
- Paste your JSON data into the input area
- Click "Generate Valibot Schema" to create the schema
- Copy the output and use it directly in your TypeScript project
Why Use This Tool?
Tips & Best Practices
- Use realistic sample data — type inference depends on actual values
- Integer values automatically use v.integer() instead of v.number()
- Wrap fields with v.optional() for fields that may be missing from the data
- Use v.pipe() to chain multiple validations like v.pipe(v.string(), v.email(), v.minLength(5))
- Valibot schemas are fully tree-shakeable — only import what you use
Frequently Asked Questions
What is Valibot?
Valibot is a lightweight, modular schema validation library for TypeScript. It validates data at runtime while providing automatic TypeScript type inference. Its functional API with namespace imports (import * as v from 'valibot') makes it tree-shakeable and ideal for bundle-size-conscious projects.
How does JSON map to Valibot types?
JSON strings map to v.string(), integers to v.integer(), floats to v.number(), booleans to v.boolean(), null to v.union([v.string(), v.null()]) or v.nullable(v.string()), arrays to v.array(v.type()), and objects to v.object({...}). Email-like strings get v.pipe(v.string(), v.email()) and URL-like strings get v.pipe(v.string(), v.url()).
What is the difference between v.optional() and v.nullable()?
v.optional() wraps a schema to allow undefined values (field can be missing), while v.nullable() wraps a schema to allow null values. For strict nullable fields, v.union([v.string(), v.null()]) is the most explicit approach. Choose the strategy that matches your API contract.
Can I use the generated schema with form libraries?
Yes! Valibot schemas work with popular form libraries. With React Hook Form, use the @hookform/resolvers/valibot resolver. With Formik, you can create a custom validation function using v.safeParse(). The generated schemas also work with conform-to/valibot for Remix/React Router.
Is my data sent to a server?
No, all processing happens entirely in your browser. Your JSON data never leaves your device.