macos - How can I remove outdated installed versions of Homebrew packages?

How can I remove outdated versions of Homebrew packages that are installed side-by-side with current versions?

Answer

The cleanup (brew cleanup) command will remove outdated installed package versions. To affect a particular package/formula, you may supply a formula name like so: brew cleanup $FORMULA. To simulate cleanup, i.e. see what would be removed, you may use the -n option: brew cleanup -n.