The common use of whitespace in web design is an excellent indicator of minimalism. This isn't to say that all websites using extra whitespace should follow a minimalistic design sense. But users often enjoy the freedom from clutter in your layout. And the difficulty for editing a layout to include whitespace is often very low.
This collection of 38 minimalist layouts is geared towards websites utilizing extra whitespace in a positive manner. There are definitely situations where you can overdo it by removing too much content, or appending wider margins than necessary. Ultimately the best look on your website will change depending on a number of factors. But check out this gallery below and see if you can brainstorm any useful ideas on whitespace design for your next project.