Use the prettier command to run Prettier from the command line. prettier [options] [file/dir/glob ...] To run your locally installed version of Prettier, prefix the command with npx or yarn (if you use Yarn), i.e. npx prettier --help, or yarn prettier --help. To format a file in-place, use --write. (Note: This overwrites your files!) In practice, this may look something like: prettier . --write Th