cm to mm & Ring Size Converter
Unit ConversionConverts the inner circumference of a ring or diameter from centimeters to millimeters, and looks up the equivalent ring size across six international sizing systems at the same time.
US / Canada Size
The nearest US / Canada ring size (rounded up, since fingers are not perfectly round).
Value (mm)
54.4
The same measurement converted to millimeters.
UK / Australia Size
N
The equivalent UK / Australia ring size.
Germany / Switzerland Size
54.4
The equivalent Germany / Switzerland ring size (circumference in mm).
France / Russia Size
54.4
The equivalent France / Russia ring size.
Japan Size
14
The equivalent Japan ring size.
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Unit Conversion calculators
Calculator Stats
Creators
Odeh Ahwal0people find this calculator helpful
Views
Helpful
Saved
Embeds
Unit Conversion calculators
Frequently Asked Questions
How is ring size determined from a measurement?
The measurement is converted to millimeters and, if you entered a diameter, to a circumference (Circumference = Diameter x Pi), then matched to the nearest standard ring-size chart row, always rounding up since a finger is not perfectly round.
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