Roboto

Roboto is a sans-serif font. It goes well with Roboto Slab, Open Sans, Lato, Playfair Display, Futura PT, Montserrat, Encode Sans, Oswald, Merriweather and Museo Sans. If you're thinking about using Roboto then try Give 21px a shot for content.

People commonly tag it as design, agency, writing, portfolio, tech, marketing, clean, blog, modern and news. You can get it from Font Squirrel, Google Web Fonts and Typekit.