Tigermoth understands the importance of size accuracy for comfort and wearability, however, ring size can vary slightly due to the design, material...and the wearer.
Common ring sizes for women:
Small N ~ 6¾
Medium P ~ 7¾
Large R ~ 8¾
Common ring sizes for men:
Small T ~ 9¾
Medium V ~ 10¾
Large X ~ 11¾
If you're still unsure, here are a few extra steps towards the comfiest possible fit:
Download this Ring Gauge pdf and hit print (making sure "actual size" is selected in the print options).
After confirming the print scale with a ruler, compare the measurments on the gauge with an existing ring or by marking a strip of card wrapped comfortably around the finger.
If in doubt between sizes, order the larger size.