What is JSON to Yup Schema Generator?
Yup is a JavaScript schema builder for value parsing and validation, widely used with React form libraries like Formik and React Hook Form. This tool converts your JSON data into Yup validation schemas automatically, handling type inference, nested objects, and email detection.
How to Use
- Set the root schema name and choose ESM or CJS module format
- Toggle "All required" to add .required() to every field, or "Detect email" to add .email() for email-like strings
- Paste your JSON data into the input area
- Click "Generate Yup Schema" to create the schema
- Copy the output and use it directly in your React project
Why Use This Tool?
Tips & Best Practices
- Use realistic sample data — type inference depends on actual values
- Integer values automatically get .integer() validation
- Null values generate yup.mixed().nullable() for optional fields
- The generated schema works directly with Formik's validationSchema prop
Frequently Asked Questions
What is Yup?
Yup is a JavaScript schema builder for value parsing and validation. It is commonly used with React form libraries like Formik and React Hook Form to define validation rules declaratively.
How does JSON map to Yup types?
JSON strings map to yup.string(), numbers to yup.number() (integers get .integer()), booleans to yup.boolean(), null to yup.mixed().nullable(), arrays to yup.array().of(...), and objects to yup.object().shape({...}). Nested objects get separate schema variables for reusability.
Can I use the generated schema with Formik?
Yes! The generated Yup schema is fully compatible with Formik's validationSchema prop. Simply import the schema and pass it to your Formik component configuration.
Does this tool send my data to a server?
No, all processing happens entirely in your browser. Your JSON data never leaves your device.