Paste valid JSON and generate reusable TypeScript interfaces or type aliases with inferred primitive, array, and nested object types. Customize naming, optional properties, readonly fields, and output style before copying the result into your project.
Strings, numbers, booleans, arrays, objects, and null values are detected from the sample. Nested objects become named definitions so the generated output remains readable and reusable.
Generated types describe the sample you provide. Review fields that can contain additional values, mixed array items, or null in real API responses.
Interfaces work well for extendable object shapes. Type aliases are useful when you prefer a consistent type-based style or plan to combine the result with unions and intersections.
Yes. Nested objects and arrays are converted into additional TypeScript definitions and referenced from the parent type.
No. TypeScript types are removed during compilation. Use a runtime schema library when untrusted data must be validated.
Yes. Select the type alias output option before generating the result.
Convert JSON data to TypeScript interfaces with smart type detection
TypeScript interface will appear here...Smart Type Detection
Automatically detects types including dates, arrays, and nested objects
Nested Interface Generation
Creates separate interfaces for nested objects
Array Type Inference
Handles arrays with mixed types and object arrays
Customizable Options
Interface vs Type, optional properties, readonly modifiers
Comment Generation
Adds helpful comments for dates and special types
Property Sorting
Optional alphabetical sorting of properties