font
It goes well with Lettera, FF Tisa, Freight Text, Calibre, Gotham Rounded, Copernicus, Lora, Geogrotesque, Calluna and Lucida Grande. If you're thinking about using Circular then try Give 60px a shot for content.
People commonly tag it as portfolio, design, bold, agency, big, writing, food, social, travel and health.
Circular on its own
28 Circular samples