Size

How to Measure Ring Size

Here’s a simple guide to measure your ring size accurately:

  1. Prepare Tools:
    • A piece of string, dental floss, or a thin strip of paper (about 1 cm wide).
    • A ruler with millimeter markings.
    • A pen and paper to record measurements.
    • (Optional) If you have a well-fitting ring, you can measure its inner diameter.
  2. Measure Your Finger:
    • Choose the Right Time: Fingers may swell slightly throughout the day. Measure in the evening or when your hands are warm for better accuracy.
    • Using String or Paper:
      1. Wrap the string or paper strip around the base of the finger where the ring will sit (usually the ring finger).
      2. Ensure it’s snug but not too tight, mimicking a comfortable ring fit.
      3. Mark where the string or paper overlaps with a pen.
      4. Lay the string or paper flat and measure the length between the marks in millimeters. This is your finger’s circumference.
    • Note: If your knuckle is larger, measure its circumference too and choose a slightly larger size to ensure the ring can slide on.
  3. Measure an Existing Ring (if available):
    • Take a ring that fits the intended finger comfortably.
    • Measure the inner diameter (straight line from one inner edge to the other) in millimeters using a ruler.
    • Exclude the ring’s edge thickness; measure only the inner circle.
  4. Compare with a Size Chart:
    • Use the measured circumference or diameter to find your ring size using the U.S. ring size chart below.
    • If your measurement falls between two sizes, opt for the larger size for comfort.
  5. Tips:
    • Measure Multiple Times: Repeat 2-3 times and take the average for accuracy.
    • Temperature Matters: Fingers are slimmer in cold weather and slightly larger when warm.
    • Ring Width: Wide rings (over 6 mm) may require a half or full size larger than narrow rings.
    • Visit a jeweler for professional sizing with a ring sizer if possible.

U.S. Ring Size Standard

Below is the U.S. ring size chart with corresponding inner circumference (mm) and inner diameter (mm):


U.S. Size Circumference (mm) Diameter (mm)
3 44.2 14.1
3.5 45.5 14.5
4 46.8 14.9
4.5 48.0 15.3
5 49.3 15.7
5.5 50.6 16.1
6 51.9 16.5
6.5 53.1 16.9
7 54.4 17.3
7.5 55.7 17.7
8 57.0 18.1
8.5 58.3 18.5
9 59.5 19.0
9.5 60.8 19.4
10 62.1 19.8
10.5 63.4 20.2
11 64.6 20.6
11.5 65.9 21.0
12 67.2 21.4
12.5 68.5 21.8
13 69.7 22.2

Additional Tips

  • International Sizing: U.S. sizes differ from other countries (e.g., UK, Japan, Europe). Check international conversion charts if needed.
  • Professional Sizing: Jewelers use ring sizing tools like sizing rings or gauges for precise measurements.
  • Online Tools: Many jewelry websites offer printable ring size charts; follow their instructions carefully.