Ring Size Guide

It is essential to know that a ‘Ring size’ refers to the inside measurement of the circumference of a ring. Knowing your correct ring size will ensure that we get things right and give you the ring that fits perfectly. 


There are various standardized systems adopted by different countries for denoting ring sizes. The chart on the right illustrates the three most common ring-size systems used in UK, USA and internationally. Australia uses the same reference for ring size as the UK.

Ring sizes change with time, and it is important to find out the correct ring size to ensure that the ring fits perfectly. The embarrassment of having a ring too small or too big, cannot be downplayed, hence we suggest you use our FREE Ring Sizer App to get the perfectly fitting ring. You will be able to give us accurate measurements in either the UK, EU or USA matrix. 

All you need to do is place your loved one’s existing ring on your phone screen, then adjust the circle until it fits the inside of the ring exactly. The app will not only help you with keeping the engagement ring or the special gift a surprise, but it will save you a trip to the jewellers or sending it back to us for resizing. 

The other option is to order our FREE Ring Sizer tool. Simply fill in your details below and sign up to our email newsletter and you can expect one of our FREE Ring Sizers within 5-7 days. This neat little gadget will give you, and us, an accurate measurement for a perfect fit. However, this service is only available for our UK clients. 

While we are confident that we can provide every sized ring, it should be noted that due to technical reasons, very small or large fitting rings may take a little more time; approximately 3-6 weeks. 

Our UK clients can use the British Standardized measurements. It consists of 26 different ring measurements, viz. A~Z. The increase from one letter to the next goes up in ring circumference by 1.25mm, with half sizes in between. 


Kindly note, we welcome returns and exchanges on rings between the sizes of J to Q; however, rings with sizes outside this range are not accepted as returns or exchanges because these rings have been especially sized for you.


Do NOT measure your ring size using an ordinary ruler or tape measure. The calibration and error due to parallax is bound to give inaccurate readings, resulting in a wrong size. We advise that you take an existing ring that fits perfectly to your local jeweller who can measure it accurately for you using a ring sizer tool. 

Another misconception and inaccurate technique is the “String approach”. In the past, many clients measure their fingers with a piece of string and then measure that string against a tape measure. While this may seem logical, it is highly inaccurate for our line of business as the string is malleable and stretchy while a ring is hard with a definite shape. 

The only fool proof method is to download our FREE RING SIZER APP or order a FREE RING SIZER via mail; alternatively, you can take an existing ring to your local jeweller and ask them to measure it for you. 

If you still need further advice, do not hesitate to email us on sales@sunshinediamond.co.uk

UK Sizes EU Sizes USA Sizes
A
B 1
C
D 2
E
F 45 3
G 46
H 47 4
I 48
J 50 5
K 51
L 52 6
M 53
N 54 7
O 56
P 57 8
Q 58
R 59
S 61 9
T 62
U 63 10
V 64
W 66 11
X 67
Y 68 12
Z 69

Sign up to the Newsletter for the chance to win a pair of diamond earrings!*

Plus early access to sales, birthday rewards & promotions.

@sunshinediamond