Converting code between TypeScript and JavaScript

Converting code between TypeScript and JavaScript is a common task in web development workflows. Whether you’re transitioning from JavaScript to TypeScript to take advantage of its additional features or integrating TypeScript code into an existing JavaScript project, seamless conversion is essential.

function add(a, b) {
return a + b;

console.log(add(5, 3));

When converting TypeScript to JavaScript, you’re essentially transpiling TypeScript code into its JavaScript equivalent. This process involves using the TypeScript compiler (tsc) to analyze and transform TypeScript syntax, type annotations, and other TypeScript-specific features into JavaScript code. The resulting JavaScript code maintains the logic and structure of the original TypeScript code but removes any TypeScript-specific constructs, making it compatible with any JavaScript runtime environment.

function greet(name: string): string {
return `Hello, ${name}!`;


On the other hand, converting JavaScript to TypeScript involves adding type annotations and other TypeScript features to existing JavaScript code. TypeScript offers gradual typing, allowing developers to progressively enhance JavaScript codebases with type safety and other TypeScript benefits. By gradually introducing TypeScript features and addressing type inconsistencies, developers can incrementally migrate JavaScript projects to TypeScript while maintaining backward compatibility with existing code.

Both TypeScript and JavaScript

Both TypeScript and JavaScript provide interoperability features that facilitate seamless integration between the two languages. TypeScript’s declaration files (*.d.ts) allow TypeScript code to interact with JavaScript libraries and frameworks, while JavaScript code can use TypeScript’s type definitions for enhanced tooling support.

Whether converting TypeScript to JavaScript or vice versa, the goal is to leverage the strengths of each language while ensuring compatibility and maintainability across the codebase. By understanding the conversion process and using the tools provided by TypeScript and JavaScript ecosystems, developers can optimize their development workflows and deliver robust, scalable applications.


About the Author: Vladislav Antoseac

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