Online Ring Size Calculator

Find Your Exact Ring Size at Home in 30 Seconds

Calibrate free using your device model or a credit/debit card for pixel-perfect accuracy.

Virtual Ring Sizer

Use this free online ring measurement tool to adjust the circle until it fits snugly around your finger, or matches the inside of a ring you own.

Or calibrate instantly by selecting your device

Ring held against the on-screen ring sizer circle to check the fit — Hold a ring you own flat against the screen and adjust the slider until the gold circle matches its inside edge.

Your Ring Size

🇮🇳 India14

🇺🇸 US7

🇬🇧 UKN

🇪🇺 EU54

🇯🇵 Japan13

🇨🇳 China13

🇦🇺 AUS7

Diameter17.3mm

Calibrate the Screen and Make It More Accurate

Place your card flat beside the screen. Drag the slider until the line matches the short side of your card (53.98mm).

Adjust rectangle height to match your card

53.98mm target

Credit card showing 53.98mm height measurement for ring size calibration

How to hold the card

Hold a real credit card flat against the screen with the short edge aligned to the line. The card gives the calibration a physical reference, so the app can match your screen's pixel density to the card's standard 53.98mm height instead of guessing from a generic on-screen size.

No card? Enter your screen size in inches:

Screen diagonal (inches)

How to Measure Ring Size with String or Paper

The easiest ring size calculator at home method — wrap a strip of paper around your finger and enter the length below. Convert your result using the ring size conversion table in inches and mm.

Enter your finger measurement

Measure the length of the paper or string that wrapped around your finger.

Tip: Use a thin strip of paper, not string - paper gives a more accurate measurement.

How to measure ring size at home using string or paper — Wrap a thin strip around your finger, mark where it overlaps, then measure that full length as the circumference.

How to Use an Existing Ring to Find Your Size

Already have a ring that fits? Match it on screen or enter its inner diameter to find your exact ring size online.

Enter the ring's inner diameter

Measure across the inside of the ring with a ruler. Enter the measurement below.

Ruler measuring the inner diameter of a ring — Lay the ring flat and measure straight across the inside edge, from one side to the other, in millimeters.

Indian Ring Size Chart

Full Indian ring size chart covering sizes 6–26, used by Tanishq, CaratLane, and BlueStone — with conversions to US, UK, EU, and mm.

India	Diameter (mm)	Circumference (mm)	US	UK	EU
6	14.1	44.3	3	F	44
7	14.5	45.6	3.5	G	46
8	14.9	46.8	4	H	47
9	15.3	48.1	4.5	I	48
10	15.7	49.3	5	J	49
11	16.1	50.6	5.5	K	51
12	16.5	51.8	6	L	52
13	16.9	53.1	6.5	M	53
14	17.3	54.3	7	N	54
15	17.7	55.6	7.5	O	56
16	18.1	56.9	8	P	57
17	18.5	58.1	8.5	Q	58
18	18.9	59.4	9	R	60
19	19.4	60.9	9.5	S	61
20	19.8	62.2	10	T	62
21	20.2	63.5	10.5	U	63
22	20.6	64.7	11	V	65
23	21	66.0	11.5	W	66
24	21.4	67.2	12	X	67
25	21.8	68.5	12.5	Y	68
26	22.2	69.7	13	Z	70
27	22.6	71.0	13.5	Z+1	71
28	23	72.3	14	Z+2	72
29	23.4	73.5	14.5	Z+3	74
30	23.8	74.8	15	Z+4	75
31	24.3	76.3	15.5	Z+5	76
32	24.7	77.6	16	Z+6	78
33	25.1	78.9	16.5	Z+7	79
34	25.5	80.1	17	Z+8	80
35	25.9	81.4	17.5	Z+9	81
36	26.4	82.9	18	Z+10	83
37	26.8	84.2	18.5	Z+11	84
38	27.2	85.5	19	Z+12	85
39	27.6	86.7	19.5	Z+13	87
40	28	88.0	20	Z+14	88

Ring Size Converter — US, UK, EU, India, mm and inches

Convert ring sizes across US, UK, EU, India, Japan, and Australia — in mm and inches — for both men's and women's ring sizes.

Dia (mm)	Inches	US	UK	EU	India	Japan	China	Australia
14.1	0.56	3	F	44	6	5	5	3
14.5	0.57	3.5	G	46	7	6	6	3.5
14.9	0.59	4	H	47	8	7	7	4
15.3	0.60	4.5	I	48	9	8	8	4.5
15.7	0.62	5	J	49	10	9	9	5
16.1	0.63	5.5	K	51	11	10	10	5.5
16.5	0.65	6	L	52	12	11	11	6
16.9	0.67	6.5	M	53	13	12	12	6.5
17.3	0.68	7	N	54	14	13	13	7
17.7	0.70	7.5	O	56	15	14	14	7.5
18.1	0.71	8	P	57	16	15	15	8
18.5	0.73	8.5	Q	58	17	16	16	8.5
18.9	0.74	9	R	60	18	17	17	9
19.4	0.76	9.5	S	61	19	18	18	9.5
19.8	0.78	10	T	62	20	19	19	10
20.2	0.80	10.5	U	63	21	20	20	10.5
20.6	0.81	11	V	65	22	21	21	11
21.0	0.83	11.5	W	66	23	22	22	11.5
21.4	0.84	12	X	67	24	23	23	12
21.8	0.86	12.5	Y	68	25	24	24	12.5
22.2	0.87	13	Z	70	26	25	25	13
22.6	0.89	13.5	Z+1	71	27	26	26	13.5
23.0	0.91	14	Z+2	72	28	27	27	14
23.4	0.92	14.5	Z+3	74	29	28	28	14.5
23.8	0.94	15	Z+4	75	30	29	29	15
24.3	0.96	15.5	Z+5	76	31	30	30	15.5
24.7	0.97	16	Z+6	78	32	31	31	16
25.1	0.99	16.5	Z+7	79	33	32	32	16.5
25.5	1.00	17	Z+8	80	34	33	33	17
25.9	1.02	17.5	Z+9	81	35	34	34	17.5
26.4	1.04	18	Z+10	83	36	35	35	18
26.8	1.06	18.5	Z+11	84	37	36	36	18.5
27.2	1.07	19	Z+12	85	38	37	37	19
27.6	1.09	19.5	Z+13	87	39	38	38	19.5
28.0	1.10	20	Z+14	88	40	39	39	20

Printable Ring Size Chart (Actual Size)

Prefer paper? Print this section with a built-in scale check and actual-size circles to compare against a ring you own.

Scale check

After printing, measure this line with a ruler. It should be exactly 50mm long.

If it measures anything other than 50mm, your print scale is off — set your printer to 100% or "Actual Size" (not "Fit to page") and print again.

Actual-size ring circles

Once the scale check above measures exactly 50mm, place a ring you own flat on top of each circle. The circle whose inner edge matches the ring's inner edge is your size.

US 5

US 6

US 7

US 8

US 9

US 10

US 11

Falls between two circles, or need a size outside US 5–11? Use the virtual sizer above for any size without a printer.

Why Accurate Ring Sizing Matters

Getting your size right affects comfort, jewelry setting integrity, and how well a smart ring can track your health.

Comfort & Safety

A ring that's too tight can pinch your finger or restrict circulation, while one that's too loose risks slipping off and getting lost.

Smart Ring Accuracy

Devices like the Oura Ring rely on a snug fit against your skin to track pulse and temperature - an incorrect size can throw off the readings.

Jeweler-Grade Settings

Prong height and stone settings are built around a specific size, so getting it right the first time avoids costly resizing later.

Averages Are Just a Starting Point

The average ring size is around US 6 for women and US 10 for men, but your actual size can vary widely - always measure your own finger.

Frequently Asked Questions

Common questions about using a ring size calculator online, measuring at home, and reading the Indian ring size chart.

What is my ring size?

Your ring size depends on your finger circumference and diameter. Use our on-screen ring sizer above to find your size instantly - no printer needed.

How do I measure my ring size at home?

Wrap a thin strip of paper around your finger, mark where it overlaps, measure the length, and enter it into our string calculator. Or use our virtual ring sizer directly on screen.

What is the Indian ring size chart?

Indian ring sizes run from 6 to 26, used by Tanishq, CaratLane, and BlueStone. India size 14 = US size 7 = UK N = EU 54 = 17.3mm diameter.

How do I use an online ring size calculator?

Start with the calibrated screen sizer or enter a measurement from string, paper, or a ring that already fits. Use our free online ring size calculator above to get instant US, UK, EU, and Indian ring sizes.

What is a virtual ring size calculator?

A virtual ring size calculator lets you size a finger or ring on screen without a printer. Calibrate to your device first, then match the on-screen circle to your finger or an existing ring.

How do I find my ring size in inches?

Measure your finger circumference in inches using a strip of paper, then enter it into our string calculator with the unit set to inches. We convert it instantly to US, UK, EU, and Indian sizes.

What is the average men's ring size?

The average men's ring size is US 10 (India 20, UK T, EU 62), with an inner diameter of approximately 19.8mm.

What is the average women's ring size?

The average women's ring size is US 6 (India 12, UK L, EU 52), with an inner diameter of approximately 16.5mm.

What's the difference between ring diameter and circumference?

Diameter is the straight-line measurement across the inside of the ring, while circumference is the distance around the inner edge. Circumference equals diameter × π (about 3.14), so a 16.5mm diameter is roughly 51.8mm in circumference. Our calculators convert automatically between both.

How do I size an Oura Ring or other smart ring?

Smart rings like the Oura Ring need a slightly snugger fit than jewelry since they track your pulse against your skin. Measure your finger in the evening after normal daily swelling, then compare the circumference from our string calculator to your smart ring brand's sizing kit before ordering.

What is Cartier ring size 54 in US sizing?

Cartier and most European brands use EU sizing, where the number is close to the inner circumference in millimeters. A Cartier size 54 (54mm circumference) converts to approximately US size 7. Check our conversion table above for the exact match to UK, EU, and Indian sizes.

What should I do if I'm between two ring sizes?

Size up rather than down. Fingers swell slightly during the day, and a ring that's a touch loose is easier to resize than one that's too tight. Add roughly a quarter size for bands 6mm or wider.

Are men's and women's ring sizes measured differently?

No, the same sizing systems (US, UK, EU, mm) apply to both. The only difference is average finger size: men's rings average around US 10, while women's average around US 6.

How accurate is an online ring size calculator compared to a jeweler?

A calibrated online calculator typically lands within about half a size of a jeweler's metal sizing ring, which is accurate enough for everyday rings. For engagement rings or other expensive, hard-to-resize pieces, confirm with a jeweler before finalizing your order.

Does ring width affect what size I should order?

Yes. Wider bands (6mm or more) press against more of your finger and feel tighter than a thin band at the same labeled size, so most jewelers recommend sizing up a quarter to half size for wide bands.

What is the best time of day to measure ring size?

Measure in the evening or after your hands have been active, since fingers are naturally a little larger then than first thing in the morning or when cold. This gives a more realistic everyday fit than a cold, early-morning measurement.

See How It Works

Watch how to measure your ring size at home in 30 seconds.

Ring Sizing Tips for Men and Women

These practical sizing tips help men's and women's ring sizes fit more comfortably, especially if you're between sizes.

Measure in the evening when fingers are usually slightly larger.
Measure the exact finger you plan to wear the ring on, since hands differ slightly.
Choose half a size up for wider bands and a standard fit for thinner bands.
If you are between sizes, size up for comfort and easier resizing.
Double-check whether your jeweler uses Indian, US, UK, or EU sizing before ordering.