These earrings are very comfortable.  They are also hypoallergenic for those allergic to nickel.  FYI, the diameter measurement goes from the outside edges of the earrings, NOT the inside edges.  I found the 11 cm earring to be slightly too big for me, so I ordered the 10 mm ones and they are perfect (great return department BTW).  But everyone's ears are different.  Overall a great product and a great company!