If you do not know your ring size, we highly recommend having your finger sized by a local jeweler and asking for your US ring size. You can also try this website, this PDF or purchase one here. We are responsible for sending you the ring size you ordered. However we cannot be responsible for determining your ring size. (Some people wear their rings loose, some tight. The size is your responsibility.) If you live in the US and need a ring sizer, please email us and we will do our best to help you!