Have you wanted to buy a ring online, but not known your ring size? It’s always best to get a professional to measure with the appropriate gauges, however if you don’t have easy access to a jeweller then you can try the following to work out your size:

Measuring Your Finger

Take a piece of stiff cardboard, plastic or thick wire and wrap it around your finger, then mark the exact spot where the ends join. Do not use a piece of string or paper, as these will bend to the shape of your finger. A piece of cereal box or similar should be about right for most rings. It is best to make the piece of card etc. the width of the new ring. With a ruler measure the length of this piece of card or wire. Read the ring size by circumference from the chart below.

After you have measured the length then tape it together and put it on your finger just like a real ring. Make it a firm fit, but be sure not to push or squeeze it because you won’t be able to do that with a real ring. Make sure it fits over the knuckle. If you have used a thin piece of wire and your new ring is a wide band you must add some size to allow for this. The reverse may also be true. If you use a wide piece of cardboard but the ring is going to be thin then take a quarter size off.

Your ring should fit your finger comfortably; snugly enough so that it will not fall off, but loosely enough to slide over your knuckle. Finger size changes depending on the time of day and the weather. For best results measure your finger size at the end of the day and when your fingers are warm (fingers are smaller in the early morning and when cold.) Measure finger size three to four times to make sure you get a correct reading.

Measuring an Existing Ring

You may already have a ring which fits the finger you are trying to measure.  In this case, measure the inside diameter of the ring. This measurement is taken across the centre of the ring from the inside of one side to the inside of the other side. Measure more than once – the largest measurement will be the correct one. Once you have found that a couple of times you can be fairly sure that it is accurate.

Measure the inside circumference of the ring. Get a stiff rectangular piece of paper as thin as possible, roll it into a tube and slide it inside the ring until it fits perfectly. Keep cutting slivers off the edges of the paper until the ends are just touching. You will then have an inside length that you can measure accurately. Allow a touch extra because the paper will have taken up a bit of space inside the ring. Measure the length of the paper.

You now have two measurements to compare with the chart. You really only need one, but using both will give greater accuracy.  Next, take the length of the inside of the ring, and mark this length on a piece of very stiff paper or thin cardboard. Tape it together so that it looks like a ring. Make it as wide as the real ring. Put this on your finger and then try the real ring on. The paper ring must be the same fit as the real ring. If you are measuring someone else’s ring on your finger, even if the rings don’t actually fit you, they will both fit on the same position on your finger. Check the inside diameter and inside circumference measurements against the chart and read the size.

 Ring Sizing Chart:

Circumference	Diameter	UK, Europe,	United States
(mm)	(mm)	& Australia	& Canada
44.2	14.1	F	3
44.8	14.3	F½
45.5	14.5	G	3½
46.1	14.7	G½
46.8	14.9	H	4
47.4	15.1	H½
48	15.3	I	4½
48.7	15.5	J
49.3	15.7	J½	5
50	15.9	K
50.6	16.1	K½	5½
51.2	16.3	L
51.9	16.5	L½	6
52.5	16.7	M
53.1	16.9	M½	6½
53.8	17.1	N
54.4	17.3	N½	7
55.1	17.5	O
55.7	17.7	O½	7½
56.3	17.9	P
57	18.1	P½	8
57.2	18.2
57.6	18.3	Q
58.3	18.5	Q½	8½
58.9	18.8	R
59.5	19	R½	9
60.2	19.2	S
60.8	19.4	S½	9½
61.4	19.6	T
62.1	19.8	T½	10
62.7	20	U
63.4	20.2	U½	10½
64	20.4	V
64.6	20.6	V½	11
65.3	20.8	W
65.9	21	W½	11½
66.6	21.2	X
67.2	21.4	X½	12
67.8	21.6	Y
68.5	21.8	Z	12½
69.1	22	Z½
69.7	22.2		13
70.4	22.4	Z+1
71	22.6		13½

(With thanks to Blue Nile and Jewellery Express.)