The easiest way to check your ring size is to purchase a ring sizer like this one on Amazon.
Another way is to measure a ring you already have with this handy website (note-you will need a credit card to make sure the scaling is right on your computer, you aren't entering your cc number or paying for anything).
Lastly, here are a few helpful tips:
- The most common ring size is 6 for the ring finger (US size).
- The most common midi ring sizes (for the middle three fingers) are 3-4.
- All your fingers will be different sizes. Don't just go off of your ring finger if you want to wear it on your middle, index finger, thumb, or pinky. Your left and right hands may also be different sizes.
- Don't measure when your fingers are cold (your fingers are smaller when cold!)
- When in doubt, if you are flexible with which finger to wear the ring on, order a size 7. It is most likely (though not guaranteed) to fit at least one of your fingers unless you know that your fingers are a good bit smaller or larger than average.