Ring Size Guide

US/CA	UK/AU	EU	Circumference (mm)	Inside Diameter (mm)
3	F	44	44.2	14.1
3.5	G	45	45.5	14.5
4	H	47	46.8	14.9
4.5	I	48	48.0	15.3
5	J ½	49	49.3	15.7
5.5	K ½	51	50.6	16.1
6	L ½	52	51.9	16.5
6.5	M ½	53	53.1	16.9
7	O	54	54.4	17.3
7.5	O ½	56	55.7	17.7
8	Q	57	57.0	18.1
8.5	Q ½	58	58.3	18.5
9	S	60	59.5	18.9
9.5	S ½	61	60.8	19.4
10	T ½	62	62.1	19.8
10.5	U ½	63	63.4	20.2
11	V ½	65	64.6	20.6
11.5	W ½	66	65.9	21.0
12	Y	67	67.2	21.4

How to Measure Your Ring Size

Method 1: Measure an Existing Ring (Recommended)

1. Select a ring that already fits comfortably on your desired finger.
2. Use a ruler to measure the inside diameter (the distance straight across the inside of the ring) in millimeters.
3. Match your measurement to the "Inside Diameter" column in our chart above.

Method 2: Measuring Your Finger

1. Wrap a flexible measuring tape or a thin strip of paper around the base of your finger.
2. Mark the exact spot where the ends meet and measure that length in millimeters.
3. Match this length to the "Circumference" column in our chart above.

Pro Tips for the Perfect Fit ✨

• Timing matters: Measure your finger at the end of the day when it is slightly larger.
• Caught between sizes? We always recommend sizing up for the most comfortable fit.
• Wider bands feel tighter: If you are choosing a thicker ring style, consider going up half a size.
• Still unsure? We’re here for you. Reach out to our team at support@cofuze.com for personalized sizing advice.

Note: UK and Australian ring sizes are the same. US and Canadian sizes are also identical.