VS Code

Zecro Minify

Minify modern JS, TS, CSS, HTML, and JSON to .min files. Offline.

Lite is free. Pro is $9, once, on Gumroad.

Before

          function greet(name) {
  return "Hi " + name;
}

.min

          function greet(n){return "Hi "+n}

Designed scene. Not a screen capture.

Zecro Minify Lite minifies a file or a selection, including on save, for modern JavaScript, TypeScript, CSS, HTML, and JSON. It writes a .min file. It runs offline.

What you get

Lite is free on the Marketplace and covers single-file minify.
Pro is $9, once, on Gumroad. It installs as a VSIX, not as a second Marketplace listing, and it requires Lite.
Pro adds batch minify by glob, source maps, watch mode, gzip and brotli size reports, and saved presets.