Svbtle uses Freight Sans for the headings and Proxima Nova for body. In contrast, OP's blog uses sans-serif for everything which is why most users probably see

Svbtle uses Freight Sans for the headings and Proxima Nova for body. In contrast, OP's blog uses sans-serif for everything which is why most users probably see it with Arial or Helvetica. Proxima Sans is a great font, but not free. The most similar free fonts would probably be either Lato or Open Sans.