Free calculator · 2 minutes

Ring Size Chart: Measure Your Ring Size at Home

Use a paper strip or a ring you already own. Type in one measurement and get your US size, EU size, inside diameter and circumference, plus the full ring size chart.

You do not need a jeweler to find your ring size. A strip of paper and a ruler get you within half a size, and a ring you already own gets you even closer. Type one measurement in and this tool gives you your US size, the EU size, and the exact diameter and circumference.

How to measure your ring size at home

Method 1: paper strip. Cut a thin strip of paper, about a quarter inch wide. Wrap it around the base of the finger, snug but not tight. Mark the spot where the paper overlaps. Lay the strip flat and measure from the end to the mark in millimeters. That is your circumference.

Method 2: a ring you own. Pick a ring that fits the same finger well. Measure straight across the inside, from one inner edge to the other, in millimeters. Do not include the metal. That is the inside diameter.

Use string, not thread. Thread stretches and gives you a size too small. Paper or non-stretch string is more accurate.

Ring size chart

US sizeDiameterCircumferenceEU / ISO
314.0 mm44.2 mm44
414.8 mm46.8 mm47
515.7 mm49.3 mm49
5.516.1 mm50.6 mm50.5
616.5 mm51.9 mm52
6.516.9 mm53.1 mm53
717.3 mm54.4 mm54.5
7.517.7 mm55.7 mm55.5
818.1 mm57.0 mm57
8.518.5 mm58.3 mm58.5
919.0 mm59.5 mm59.5
1019.8 mm62.1 mm62
1120.6 mm64.6 mm64.5
1221.4 mm67.2 mm67
1322.2 mm69.7 mm70

The most common women’s ring sizes in the US are 6 to 7. That is a useful sanity check: if your measurement says size 3 or size 12, measure again before you order.

Ring size chart in cm

Measured your finger or a ring in centimeters? Use this chart to turn cm into a ring size. Circumference is the distance around the inside of the ring, and diameter is the distance straight across the inside. If you measured in millimeters, move the decimal one place: 52 mm is 5.2 cm.

USUKCircumferenceDiameter
3F4.42 cm1.40 cm
3.5G4.55 cm1.44 cm
4H4.68 cm1.48 cm
4.5I4.80 cm1.52 cm
5J½4.93 cm1.57 cm
5.5K½5.06 cm1.61 cm
6L½5.19 cm1.65 cm
6.5M½5.31 cm1.69 cm
7N½5.44 cm1.73 cm
7.5O½5.57 cm1.77 cm
8P½5.70 cm1.81 cm
8.5Q½5.83 cm1.85 cm
9R½5.95 cm1.90 cm
9.5S½6.08 cm1.94 cm
10T½6.21 cm1.98 cm
10.5U½6.34 cm2.02 cm
11V½6.46 cm2.06 cm
11.5W½6.59 cm2.10 cm
12Y6.72 cm2.14 cm
12.5Z6.85 cm2.18 cm
13Z+16.97 cm2.22 cm

UK and Australian ring sizes use letters instead of numbers, so a US 7 is about an N½. If your cm measurement falls between two sizes, choose the larger one.

Get the fit right

Measure at the end of the day. Fingers swell in the afternoon and in warm weather, and shrink in the cold and first thing in the morning. An evening measurement is the safest.

Mind the knuckle. If your knuckle is wider than the base of your finger, measure both. Pick a size that slides over the knuckle, or the ring will never go on.

Wide bands need a bigger size. A band 6 mm or wider covers more skin and feels tighter. Go up half a size.

Between sizes, go up. A ring that is slightly loose can be fixed with a small sizer insert. A ring that is too tight just stays in the drawer.

Ring size by finger

Every finger is a different size. Your ring finger is usually about half a size smaller than your middle finger, and your dominant hand is usually a quarter to half a size larger than the other. Always measure the exact finger the ring is for.

Stacking rings? Measure the finger once and buy all the stack in the same size, unless one ring is much wider than the others. For more ways to style your hands, see our nail colors for your skin tone and the nail shape quiz.

Frequently Asked Questions

How can I measure my ring size at home? −
Wrap a thin strip of paper around the base of your finger, mark where it overlaps, and measure the strip flat in millimeters. That circumference matches a size on the chart. You can also measure the inside of a ring that already fits.
What is the most common ring size for women? −
In the US, most women wear between a size 6 and a size 7. If your measurement comes out far from that, it is worth measuring again before you order.
Should I size up or down if I am between sizes? −
Size up. A slightly loose ring can be fixed with a small sizer insert, but a ring that is too tight will not go over the knuckle.
Does a wide band need a bigger ring size? −
Yes. Bands 6 mm or wider cover more skin and feel tighter, so go up about half a size.
When is the best time to measure ring size? −
In the evening, at room temperature. Fingers are slightly larger later in the day and in warm weather, and smaller in the cold.
Is my ring size the same on both hands? −
Not usually. Your dominant hand is often a quarter to half a size bigger. Measure the exact finger on the exact hand the ring is for.

Keep going: pick your metal with the undertone finder, and your nail look with the nail shape quiz.