Blue Diamond

Ring Size Guide

Find your ring size at home or visit a jeweller. We use EU/CH sizes.

Measure at home

  1. Wrap a piece of string or a strip of paper around the base of your finger.
  2. Mark where the string/paper overlaps.
  3. Measure the length in millimetres.
  4. Compare with the size chart below (inner diameter) or use an online ring size calculator.

Visit a jeweller

The most accurate way is to have your finger measured at a jeweller. Many jewellers offer this free of charge.

Size chart

Common sizes (EU/CH is our standard):

EU / CHUSUKInner diameter
505J15.7 mm
525.5K16.2 mm
546L16.7 mm
566.5M17.2 mm
587N17.7 mm
607.5O18.2 mm
628P18.7 mm
648.5Q19.2 mm
669R19.7 mm

Tips

  • Measure in the evening when fingers are slightly larger.
  • Measure the finger you'll wear the ring on.
  • For wider bands, you may need half a size larger.
  • Knuckles can be larger than the base – ensure the ring can pass over.

Unsure? Our concierge can help. Contact us.

Ring Size Guide | Blue Diamond | Blue Diamond