Jewelry & Ring Sizing
Ring Size Conversion Chart
Convert ring sizes across US, UK, and EU standards. Compare inside diameter and circumference millimeters to buy rings online with 100% confidence.
Select US Ring Size:
Ring Size Conversion Profile
US Size 7 (Women Common)
Diameter: 17.3 mm (0.682")
UK & Australia (Letter Scale):
Size N 1/2
EU / ISO Circumference:
54.4 mm
Inside Diameter:
17.3 mm
Ring Sizing Golden Rules
Measure at the End of the Day
Fingers are naturally smaller in the cold morning and swell up to half a size larger in warm evening temperatures.
Account for Knuckle Clearance
If your knuckle is noticeably larger than the base of your finger, choose the half size in between so the ring slides over without getting stuck.
Wide Band Rule (>6mm width)
Wide wedding bands (6mm to 8mm) fit significantly tighter on the finger than skinny 2mm engagement bands; order 1/2 size larger for wide bands.