Kepler is a serif font. It goes well with Proxima Nova, Soleil, SS Standard, Avant Garde Gothic ITC, Futura PT, Leitura News, Europa, Times, Menlo and SS Social. If you're thinking about using Kepler then try 54px for headers. Give 18px a shot for content.

People commonly tag it as tech, event, bold, blog, design, clean, serif, agency, big and contrast. You can get it from, Fontspring and Typekit.

In action

7 Kepler samples