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No — Kepler isn’t listed as a free font. Adobe releases it, so licence options and pricing sit on their site.
Kepler is a serif typeface from Adobe.
Start with Adobe’s other releases — Source Serif. They come from the same studio that drew Kepler, and A1 has 3 websites using them.
Named after the German Renaissance astronomer, Kepler is a contemporary type family created by Adobe type designer Robert Slimbach in the tradition of classic modern 18th-century typefaces. Traditionally, modern typefaces are known for their cool intellectual quality, but Slimbach’s Kepler captures the modern style in a humanistic manner.
A1 features 1 website using Kepler. It leans towards Colourful, Clean, and Gradients design styles, and it’s most often built with Wix.