Measure Current Ring
Select a ring that properly fits the intended finger. A ring should fit your finger comfortably; snug enough so that it will not fall off, but loose enough to slide over your knuckle.
Engagement and wedding rings are traditionally worn on the ring finger on the left hand in Australia.
Measure the internal diameter of the ring as shown in the diagram in millimetres.
Measure your ring 3 to 4 times to eliminate any errors.
Refer to the International Ring Size Chart. On the left-hand vertical axis is the millimetre measurement.
Pick the country where you live from across the top of the chart, then follow it down to where it meets your mm size measurement. This will give you the ring size.
E.G. If your internal ring size measures 16.9 mm, it is a size 53 in Europe, a size M 1/2 in the UK and Australia, a size 6 1/2 in the US and Canada, a size 13 in Japan, a size 14.5 in Hong Kong, and a size 14 in Switzerland.
If the ring measurement falls between two sizes, order the larger size.
Tips For Buying A Ring As A Surprise
Ask your loved ones’ friends or mother if they know his /her finger size.
Borrow one of your loved ones’ rings (from the correct finger) and use the ring measurements in the International Ring Size Chart to the right to determine its size.