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How to use JS to TypeScript

Paste your JavaScript function, and the tool adds inferred TypeScript type annotations to its parameters and return value.

Frequently asked questions

What TypeScript features are added?

The tool adds basic type annotations to function parameters and return types, converts var to let/const, and adds interface suggestions.

Is the output production-ready TypeScript?

The output is a starting point. You'll need to refine types, add generics, and handle edge cases for production TypeScript code.

Do I need to know TypeScript to use this?

Basic TypeScript knowledge helps. The tool generates simple type annotations that you can then customize and improve.

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