Do not know your ring size?
Here is simple method may can help you.
First, please use a st ring or paper bar with 1-2 centimeter of width to wrap your intended finger to link up a circle. Second, make a sign by pen on its superposition of this wrap string or paper bar. Third, use a ruler to measure the length between the marginal beginning and the pen sign. Then, according this measure length to find your ring size by the following data.
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Size # Circumference Diameter Size # Circumference Diameter
Size 3 44.0mm 14.0mm Size 8.5 58.4mm 18.6mm
Size 3.5 45.2mm 14.4mm Size 9 59.7mm 19.0mm
Size 4 46.5mm 14.8mm Size 9.5 60.9mm 19.4mm
Size 4.5 47.8mm 15.2mm Size 10 62.2mm 19.8mm
Size 5 49.0mm 15.6mm Size 10.5 63.5mm 20.2mm
Size 5.5 50.3mm 16.0mm Size 11 64.7mm 20.6mm
Size 6 51.7mm 16.45mm Size 11.5 66.0mm 21.0mm
Size 6.5 53.1mm 16.9mm Size 12 67.2mm 21.4mm
Size 7 54.3mm 17.3mm Size 12.5 68.5mm 21.8mm
Size 7.5 55.6mm 17.7mm Size 13 69.7mm 22.2mm
Size 8 57.2mm 18.2mm Size 13.5 71.0mm 22.6mm
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Considering heat expansion and cold contraction, the proper size of ring should be just fit for your finger in summer and a little bit loose in winter.
