Ring Size Guide

Finding the perfect ring size is essential for both comfort and security. At The Altered Carbon, we want your ring to feel as perfect as it looks. Use our guide below to determine your ideal size with confidence.

Method 1: Measure an Existing Ring Method 1: Measure an Existing Ring

If you already own a ring that fits the intended finger:

Place the ring on a flat surface
Measure the inner diameter (in mm) using a ruler
Match the measurement with the size chart below

Method 2: Measure Your Finger Method 2: Measure Your Finger

Using a strip of paper or thread:

Wrap it around the base of your finger
Mark where it overlaps
Measure the length (in mm)
Compare with the circumference in the chart

💡 Tip: Measure your finger at the end of the day when it’s slightly larger for better accuracy.

Too Loose

Too Tight

Just Right

Find Your Perfect Fit with Our Printable Ring Sizer

Not sure about your ring size? Use our easy printable ring sizer to measure accurately at home and find your perfect fit before you order.

Get Printable Sizer

Ring Size Conversion Chart

All of our rings are crafted in standard US sizes. View the chart below to see how US sizes map to finger circumference and convert to international sizes. Engagement rings, wedding bands, and fashion rings all follow the same size format.

IN	MM	US, Canada, Mexico	UK, AU, NZ, SA	France	Germany, Russia, Ukraine, Asia	India, China, Japan, S.A., Turkey, Israel	Italy, Spain, Neth., Switz.
1.74	44.2	3	F	44	14	4	4 5/8
1.78	45.0	3.25	F 1/2	45	14 1/4	—	4 7/8
1.79	45.5	3.5	G	45.5	14 1/2	—	5 1/4
1.82	46.1	3.75	G 1/2	46	14 3/4	6	5 1/2
1.85	46.8	4	H	47	15	7	7 1/8
1.87	47.4	4.25	H 1/2	47.5	15 1/4	—	7 3/8
1.89	48.0	4.5	I	48	15 1/4	—	7 5/8
1.92	48.7	4.75	J	48.5	15 1/2	—	8 3/8
1.94	49.3	5	J 1/2	49	15 3/4	—	8 5/8
1.97	50.0	5.25	K	50	16	—	9 5/8
1.99	50.6	5.5	K 1/2	50.5	16 1/4	11	10 1/8
2.04	51.8	6	L 1/2	51.5	16 1/2	12	11 5/8
2.07	52.5	6.25	M	52.5	16 3/4	—	12 1/8
2.09	53.1	6.5	M 1/2	53	17	13	12 3/4
2.12	53.8	6.75	N	54	—	—	13 3/8
2.14	54.4	7	N 1/2	54.5	17 1/4	14	14 1/8
2.17	55.1	7.25	O	55	17 1/2	14	14 5/8
2.19	55.7	7.5	O 1/2	55.5	17 3/4	15	15 1/8
2.22	56.3	7.75	P	56.5	18	15	15 5/8
2.24	57.0	8	P 1/2	57	18	16	16 1/8
2.27	57.6	8.25	Q	58	18 1/4	—	16 3/8
2.29	58.3	8.5	Q 1/2	58.5	18 1/2	17	17 3/4
2.32	58.9	8.75	R	59	18 3/4	18	18 3/8
2.34	59.5	9	R 1/2	60	19	18	19 1/8
2.37	60.2	9.25	S	60.5	19 1/4	19	19 5/8
2.39	60.8	9.5	S 1/2	61	19 1/2	19	20 1/4
2.42	61.4	9.75	T	62	19 3/4	20	21 1/8
2.44	62.1	10	T 1/2	63	19 3/4	20	21 1/2
2.47	62.7	10.25	U	63.5	20	21	22 3/8
2.49	63.4	10.5	U 1/2	64	20 1/4	22	23 3/4
2.52	64.0	10.75	V	65	20 1/2	23	24
2.54	64.6	11	V 1/2	65	20 3/4	23	24 5/8
2.57	65.3	11.25	W	66	21	24	25 1/4
2.59	65.9	11.5	W 1/2	66	21	24	25 1/4
2.62	66.6	11.75	X	—	21 1/2	—	27 5/8
2.65	67.2	12	X 1/2	67.5	21 1/2	25	26 1/2
2.68	68.1	12.25	Y	68	21 3/4	—	27 3/4
2.71	68.5	12.5	Z	69	21 3/4	26	27 3/4
2.75	69.1	12.75	Z 1/2	69.5	—	27	28 3/8
2.75	69.7	13	—	70	22	27	29

Your cart is empty

Your cart

Estimated total