Lato

Lato is a sans-serif font. It goes well with Playfair Display, Open Sans, Roboto, Proxima Nova, Montserrat, Ubuntu, Georgia, Droid Serif, Arial and PT Sans. If you're thinking about using Lato then try 20px for headers. Give 18px a shot for content.

People commonly tag it as design, portfolio, modern, tech, writing, agency, list, clean, photo and ecommerce. You can get it from Font Squirrel, Google Web Fonts, Open Font Library and Typekit.