Convert finger circumference (cm/mm) or diameter to US, UK, EU, and Asian ring sizes.
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Wrap a thin strip of paper or string snugly around your finger knuckle and measure length in centimeters or millimeters.
Choose whether you measured circumference (cm/mm) or inside diameter (mm/in).
Instantly review your exact ring size for US & Canada, UK & Australia, European Union (ISO 8653), and East Asia.
Wrap paper around the base of your finger, mark where it overlaps, and measure the length with a ruler in millimeters. For best fit, measure at room temperature at the end of the day.
The EU / ISO 8653 standard directly equals the inside circumference of the ring band in millimeters (e.g. 54 mm circumference = Size 54).
Jewelers recommend sizing up to the next half size (or quarter size) for wider bands and comfort fit.
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