We use standard US sizing for all our rings. The easiest way to make sure you get the right size is to measure the inside diameter of a ring that fits you well. If you don't have a ring handy you can also measure your finger by holding a string around it and then measure the length of that piece of string. Please note that we do not except returns/exchanges for size so choose carefully.
If you have any questions please don't hesitate to contact us at firstname.lastname@example.org