International conversion · US · UK · EU · JP

Ring size chart: US, UK, EU and millimetres.

Convert US, UK, EU and Japanese ring sizes side-by-side, with inside circumference and diameter in millimetres. For example, a US size 7 is UK N ½, EU 54, 17.3 mm in diameter and 54.4 mm in circumference. Not sure of your size? Use the free virtual ring sizer first.

Inside Circumference US / CA / MX🇺🇸 🇨🇦 🇲🇽 UK / AU / IE / NZ / ZA🇬🇧 🇦🇺 🇮🇪 🇳🇿 🇿🇦 France🇫🇷 DE / RU / UA🇩🇪 🇷🇺 🇺🇦 IN / CN / JP / SA / TR / IL🇮🇳 🇨🇳 🇯🇵 🇧🇷 🇨🇱 🇦🇷 🇹🇷 🇮🇱 IT / ES / NL / CH🇮🇹 🇪🇸 🇳🇱 🇨🇭
IN MM
1.7444.23F441444
1.7744.83.25F ½44.62514.254.625
1.7945.53.5G45.2514.555.25
1.8246.13.75G ½45.87514.7565.875
1.8446.84H46.51576.5
1.8747.44.25H ½47.12515.257.125
1.89484.5I47.7515.587.75
1.9248.74.75J48.3758.375
1.9449.35J ½4915.7599
1.97505.25K49.625169.625
1.9950.65.5K ½50.2516.251010.25
2.0251.25.75L50.8751110.875
2.0451.96L ½51.516.51211.5
2.0752.56.25M52.12516.7512.125
2.0953.16.5M ½52.75171312.75
2.1253.86.75N53.37513.375
2.1454.47N ½5417.251414
2.1755.17.25O54.62517.514.625
2.1955.77.5O ½55.2517.751515.25
2.2256.37.75P55.87515.875
2.24578P ½56.5181616.5
2.2757.68.25Q57.12518.2517.125
2.2958.38.5Q ½57.7518.51717.75
2.3258.98.75R58.37518.7518.375
2.3459.59R ½59191819
2.3760.29.25S59.62519.2519.625
2.3960.89.5S ½60.2519.51920.25
2.4261.49.75T60.87519.7520.875
2.4462.110T ½61.5202021.25
2.4762.710.25U62.12520.252122.125
2.4963.410.5U ½62.7520.52222.75
2.526410.75V63.37523.375
2.5464.611V ½6420.752324
2.5765.311.25W64.62524.625
2.5965.911.5W ½65.25212425.25
2.6266.611.75X65.87525.875
2.6567.212X ½66.521.252526.5
2.6868.112.25Y67.12521.527.125
2.7168.512.5Z67.7521.752627.75
2.7269.112.75Z ½68.37528.375
2.7569.71369222729
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Ring size chart FAQ

Getting the conversion right.

How do I find my ring size on the chart?

Measure the inside diameter of a ring that fits, or your finger circumference in millimetres. Find that number in the chart and read across to the regional size you need.

Is ring diameter the same as circumference?

No. Diameter is the straight-line distance across the ring's inside. Circumference is the distance around its inside. Use the column that matches the measurement you took.

What if I am between two sizes?

Choose the larger size when the smaller one would be tight over your knuckle. Wide bands can also need extra room. Confirm expensive or non-resizable rings with a jeweller.

How to read this chart

Diameter, circumference and what they mean.

Inside Diameter (IN / MM)

The straight-line distance across the inside of a ring. A US 8 ring has an inner diameter of about 18.14 mm (0.714 in). Jewellers most often measure with a ring mandrel that reads this directly.

Inside Circumference (MM)

The distance around the inside of a ring — what your finger actually measures. A US 8 has a circumference of about 57 mm. This is the metric most international standards (EU, JP) are based on.

US / Canada / Mexico (numeric)

North American sizes use whole and quarter-sizes from 3 through 13. Most women's rings fall between US 5 and 7, most men's between US 9 and 11.

UK / AU / IE / NZ / ZA (letter)

British and Commonwealth countries use a letter system from F to Z, often with ½ sizes (e.g. M½). One UK letter step ≈ ½ US size.

EU · France · Germany

Continental Europe usually uses the circumference in millimetres directly — so an EU 57 = 57 mm circumference = US 8.

Japan · China · India · South America

These regions use a numeric scale where 1 step ≈ 0.32 mm increase in circumference. A JP 16 ≈ US 8.

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