If you want to wear a single ring, check the size of a ring you already wear on this finger. If you want to wear stackable rings, please, consider that the rings should be one size bigger than your regular size.

US SIZE	EUROPEAN SIZE	Diameter (mm)
4	6.75	14.9
4 1/2	8	15.3
5	9.25	15.7
5 1/2	10.5	16.1
6	11.75	16.5
6 1/2	13.25	16.9
7	14.5	17.3
7 1/2	15.75	17.7
8	17	18.1
8 1/2	18.25	18.5
9	19.5	19.0
10	22	19.8