EU ring size 68 in US, UK & Japan

EU/ISO ring size 68 is an inner circumference of about 68 mm (68.5 mm exactly) — that equals US 12.5, UK Z and Japan 26, with an inner diameter of 21.79 mm.

21.79 mm inner Ø
Illustrative — screen scale varies. Use the true-scale ring below for a real measurement.
EU / ISO
68
US / Canada
12.5
UK / AU
Z
Japan
26
CH / IT / ES
28
Diameter
21.79 mm
Circumference
68.5 mm
Why EU 68 looks larger than US 12.5

Under ISO 8653, the EU (and ISO) ring size number is the ring's inner circumference in millimetres. So EU 68 means the band measures about 68 mm all the way around — a circumference, not a diameter. That's why EU numbers are so much larger than US numbers for the same finger, and why an EU size can be read straight off a millimetre measurement.

True-to-scale ring Printed at 100%, the inside of this ring is 21.79 mm across.

Convert the other way with the EU to US ring size chart, open the US size 12.5 page, see the full chart, or use the converter.

Frequently asked questions

Why does EU 68 use a circumference number?

EU/ISO 68 follows the published circumference convention: about 68 mm around the inside (68.5 mm in this chart), corresponding to a 21.79 mm inner diameter.

How should I confirm EU 68 before ordering?

Check the retailer's own chart and confirm the 21.79 mm inner diameter with a physical sizer or a ring that already fits. Converted labels are a starting point, not a fit guarantee.