Babel

Babel is an open-source JavaScript compiler that lets you write modern code while ensuring its compatibility with older environments. It transforms the latest JavaScript syntaxes (and JSX) into versions understood by older browsers and engines, a role long central to the front-end toolchain.

What is Babel used for?

Babel is used to stop worrying about compatibility: developers write with the newest JavaScript features, and Babel translates them into code that runs everywhere. It also handles React JSX transformation and integrates with build tools like Vite and legacy bundlers.

Is Babel still necessary?

Its role has evolved: modern browsers natively support many recent features, and tools like Vite include their own fast transforms. Babel stays useful for targeting older environments and for certain specific transformations, even if it is less systematically front and center.

How much does Babel cost?

Babel is entirely free and open source, under the MIT license. The compiler and its plugins are free, with no paid tier. The project is maintained by the community and sponsors, at no cost to developers.