Developer tools
Free toolJavaScript Converter
Convert JavaScript to TypeScript, free and online
JavaScript Converter is a free online tool that converts JavaScript source code to TypeScript using deterministic AST transforms. It handles automatic type inference, CommonJS-to-ES-module rewriting, JSDoc-to-type conversion, class-property detection, and tsconfig generation, and also renames .js/.jsx files to .ts/.tsx. A free Windows desktop app is available in addition to the browser tool.
Get JavaScript Converter
DownloadFree to useView PricingPlans & pricingVisit Websitejavascriptconverter.comWhat you get
Key capabilities of JavaScript Converter.
Module Rewriting
Converts CommonJS require and module.exports into ES Module import and export syntax.
JSDoc Type Inference
Turns JSDoc @param and @returns annotations into native TypeScript types.
Class Property Detection
Detects class properties from constructor assignments and hoists static members.
Automatic File Renaming
Renames .js files to .ts and .jsx files to .tsx during conversion.
Official site
Full documentation, live demos, and support live on javascriptconverter.com.
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