javascript transpilers
Short for "transformation compiler," is a tool that converts source code written in one programming language (such as ES6+ JavaScript) into another, usually older or more widely supported version (like ES5 JavaScript), making it compatible with a broader range of browsers.
in 2026 the standard for TS projects is to have SWC for dev builds (fast hot module replacement) and for safety use tsc to check types (--noEmit to tell TS to not bother creating JS files). Your IDE also uses the TS LSP (which uses tsc) to validate types.
SWC can read TS files and transform them to JS but it completely ignores and strips types.
1. SWC (Speedy Web Compiler)
SWC has largely overtaken Babel as the preferred transpiler for performance-conscious teams.
- Language: Rust.
- Usage: It is the default transpiler for Next.js and Deno. It is roughly 20x faster than Babel on a single core.
2. Babel (The Pioneer)
Babel is the "grandfather" of transpilers.
- Why it's still used: Its plugin system is unparalleled. If you need to support a highly specific or experimental JS proposal, Babel usually has the plugin first.
- Status in 2026: Often relegated to legacy support or projects that require very specific transformations not yet supported by SWC.
3. Oxc (The Newest Contender)
The Oxc (Oxidized Compiler) project is the "new kid on the block" gaining rapid traction.
- Why it's popular: It aims to be even faster than SWC by focusing on memory efficiency and extreme parallelization.
- Components: It includes a suite of tools like
oxlint(a replacement for ESLint) and a parser that is currently the fastest in the ecosystem.
4. TypeScript (TSC)
While primarily a type-checker, the tsc compiler is still a very popular transpiler, especially for small projects or libraries where a separate build step (like Babel/SWC) might feel like overkill.