The most accurate way to measure ring size is by using a ring-measurement tool.
They are typically inexpensive, and there are many options online. Ring-sizing tools fall into two categories: a thin measuring tape or a keyring lined with a gradient of ring sizes. The measuring tape type ring sizer can be looped around your finger and tightened or loosened with a belt mechanism. The keyring type ring sizer has metal loops for each ring size, so you can try each one on your finger until you find the best fit. Ring sizers can be helpful to keep on hand to measure when shopping for rings for friends and family.
How to Measure Ring Size with a Sizing Chart
Print out our true-to-size ring size chart on 8.5 x 11 inch paper, and place your ring on the circles until you find the one that matches up with the inside circumference of your ring.
How to Measure Your Ring Size with String
1. Take a length of floss or string and wrap it around the base of your finger.
2. Mark where the floss or string first overlaps with a pen.
3. Stretch the length of string out along a ruler or measuring tape, and take down the length in millimeters.
4. The length you measured is the circumference of your finger—to calculate the diameter, divide the circumference by pi (dividing by 3.14 will work).
5. Download our ring size chart to compare the diameter of your finger to the standard ring sizes.
Ring Sizing Tips
Here are a few pointers to keep in mind when you measure your ring size:
- Consider the knuckle: If you know your knuckle is on the larger side, order half a size bigger than what your finger alone indicates, otherwise you won't be able slide a ring into the right place.
- Ensure accuracy with multiple tries: we recommend measuring your finger three to four different times because finger size fluctuates with changes in temperature: It can be smaller when your body is cold, and more swollen if you are overheated.
- Measure the finger you want to wear the ring on: Your ring finger may be smaller or larger on one hand than the other, so make sure to measure the finger you intend to wear the ring on for a comfortable fit.