Letter Conversions

Ring Size Letters to Numbers

Converting the UK alphabetical sizing system (A-Z) into the US numerical system (1-15).

Is Z the Biggest Ring Size?

While "Z" sounds like the absolute end of the scale, it is actually not the largest ring size. Z is a US 12.5, which is quite large, but many men require larger sizes.

The UK system continues past Z using numbers, such as Z+1, Z+2, up to Z+6 (which equals a US size 15). So no, Z is not the biggest!

Quick Conversion Guide

J = US 4.75
L = US 5.75
N = US 6.75 (Average Women)
Q = US 8.25 (Average Men)
T = US 9.75
Z = US 12.5

Written by Evelyn Moore

Evelyn is a certified GIA Gemologist with over a decade of experience in fine jewelry sizing and design. She ensures all conversion charts and measuring advice strictly adhere to ISO 8653 standards.