You can easily and confidentially measure your own finger size from 0-17 with accurate full, half, and quarter sizes. You can choose between the free PDF download (please provide your email address) or purchase our Multi-sizer sizing finger belt. We recommend the latter as that would be the most accurate, however, as long as the size is within a +/-1 size difference, that would be fine (only applicable to non-eternity designs).
If this is a surprise, measure the diameter of the a current ring and send it to us. We will help you convert it to a ring size. Make sure to take note of which finger the ring you are measuring is worn on, as different fingers are different sizes.
More sizing tips and important considerations can be found here.