Convert JSON to TypeScript interfaces instantly. Handles nested objects, arrays, optional properties, and union types. Generate clean, type-safe TypeScript code in seconds.
Paste your JSON and instantly get TypeScript interfaces. The tool analyzes your data structure and generates type-safe interfaces with proper nesting and type inference.
Automatically detects strings, numbers, booleans, arrays, objects, null, and union types. Handles arrays of mixed types and creates separate interfaces for nested objects.
When processing arrays of objects, detects which properties appear in all objects versus only some, and marks inconsistent properties as optional with the ? modifier.
Toggle export statements on or off, customize interface names, copy to clipboard, or download as a .ts file. Ready to paste into your TypeScript project immediately.
TypeScript interfaces provide static type checking for JavaScript objects, helping you catch errors at compile time instead of runtime. When working with API responses, configuration files, or any JSON data, manually writing TypeScript interfaces can be time-consuming and error-prone. This tool automates the process by analyzing your JSON structure and generating accurate, well-formatted TypeScript interfaces.
The converter parses your JSON data and infers TypeScript types for each property. For primitive values, it detects whether they are strings, numbers, booleans, or null. For arrays, it analyzes the element types and creates array type notation (e.g., string[] or User[]). For nested objects, it creates separate named interfaces and references them in the parent interface. The result is clean, idiomatic TypeScript code that follows best practices.
This tool handles complex JSON structures including deeply nested objects, arrays of objects with varying properties, union types for mixed arrays, and optional properties. You can customize the root interface name, toggle export statements, and download the output as a ready-to-use TypeScript file. The converter also preserves property order and generates meaningful interface names based on property keys.
Type[]. For arrays with mixed types, it creates union types like (string | number)[]. For arrays of objects, it creates a separate interface and references it as Interface[].
? modifier in the TypeScript interface.
export keyword, making them ready to import in other TypeScript files. You can also copy the output to clipboard or download it as a .ts file.
string, number, boolean, null, arrays, objects, and union types. It also handles Date objects, any type for unknown structures, and creates proper interface references for nested objects.
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