Compile .less files to .css using the command line

Heads up! If the command line isn't your thing, learn more about GUIs for Less.

Install with npm

npm install less -g

The -g option installs the lessc command available globally. For a specific version (or tag) you can add @VERSION after our package name, e.g. npm install less@2.7.1 -g.

Alternatively, if you don't want to use the compiler globally, you may be after

npm i less --save-dev

This will install the latest official version of lessc in your project folder, also adding it to the devDependencies in your project's package.json.

Periodically, as new functionality is being developed, lessc builds will be published to npm, tagged as beta. These builds will not be published as a @latest official release, and will typically have beta in the version (use lessc -v to get current version).

Since patch releases are non-breaking we will publish patch releases immediately and alpha/beta/candidate versions will be published as minor or major version upgrades (we endeavour since 1.4.0 to follow semantic versioning).

The binary included in this repository, bin/lessc works with Node.js on *nix, OS X and Windows.

Usage: lessc [option option=parameter ...] <source> [destination]

lessc [option option=parameter ...] <source> [destination]

If source is set to `-' (dash or hyphen-minus), input is read from stdin.

Compile bootstrap.less to bootstrap.css

lessc bootstrap.less bootstrap.css

For all other options, see Less Options.

lessc -s lessc --silent

Stops any warnings from being shown.

lessc -v
lessc --version

Prints a help message with available options and exits.

lessc -M
lessc --depends

Outputs a makefile import dependency list to stdout.

Deprecated.

lessc --no-color

In v2 of less, Clean CSS is no longer included as a direct dependency. To use clean css with lessc, use the clean css plugin.