Ring Sizes

The scale of ring sizes varies from country to country. The tables below gives a table of approximate equivalents in different countries. The left most 3 columns will be exact, but as there is no exact equivalent between most scales the columns to the right show the closest match, not an exact one. Please note this is intended as a guide only. Also be aware that no country exclusively uses a particular scale, so you may for example often find US sized rings in the UK.

The UK column covers: United Kingdom, Ireland, Australia, New Zealand, South Africa

The US column covers: United States, Canada, Mexico

EU ISO column covers: Most European countries

The Italy column covers: Italy, Spain, Switzerland, Netherlands, Brazil, India

The Russia column covers: Russia, Ukraine, Belarus

The Japan column covers: Japan, China, Korea, Hong Kong, Taiwan, Singapore.

Diameter and Circumference measurements are in mm

UK to other sizes

UK Size	Diameter	Circumference	US	EU ISO	Italy	Russia	Japan
A	11.937	37.5	0½	37½		12
A¼	12.036	37.813	0½	37¾		12
A½	12.136	38.125	0½	38¼		12¼
A¾	12.235	38.438	0¾	38½		12¼
B	12.335	38.75	0¾	38¾		12¼
B¼	12.434	39.063	1	39		12½
B½	12.533	39.375	1	39½		12½
B¾	12.633	39.688	1¼	39¾		12¾
C	12.732	40	1¼	40	0	12¾
C¼	12.832	40.313	1½	40¼	0¼	12¾
C½	12.931	40.625	1½	40¾	0¾	13
C¾	13.031	40.938	1¾	41	1	13	1
D	13.13	41.25	1¾	41¼	1¼	13¼	1½
D¼	13.23	41.563	2	41½	1½	13¼	1¾
D½	13.329	41.875	2	42	2	13¼	2
D¾	13.429	42.188	2¼	42¼	2¼	13½	2¼
E	13.528	42.5	2¼	42½	2½	13½	2½
E¼	13.628	42.813	2½	42¾	2¾	13¾	3
E½	13.727	43.125	2½	43¼	3¼	13¾	3¼
E¾	13.827	43.438	2¾	43½	3½	13¾	3½
F	13.926	43.75	2¾	43¾	3¾	14	3¾
F¼	14.026	44.063	3	44	4	14	4
F½	14.125	44.375	3	44½	4½	14¼	4½
F¾	14.224	44.688	3¼	44¾	4¾	14¼	4¾
G	14.324	45	3¼	45	5	14¼	5
G¼	14.423	45.313	3½	45¼	5¼	14½	5¼
G½	14.523	45.625	3½	45¾	5¾	14½	5½
G¾	14.622	45.938	3¾	46	6	14½	5¾
H	14.722	46.25	3¾	46¼	6¼	14¾	6¼
H¼	14.821	46.563	4	46½	6½	14¾	6½
H½	14.921	46.875	4	47	7	15	6¾
H¾	15.02	47.188	4¼	47¼	7¼	15	7
I	15.12	47.5	4¼	47½	7½	15	7¼
I¼	15.219	47.813	4½	47¾	7¾	15¼	7¾
I½	15.319	48.125	4½	48¼	8¼	15¼	8
I¾	15.418	48.438	4¾	48½	8½	15½	8¼
J	15.518	48.75	4¾	48¾	8¾	15½	8½
J¼	15.617	49.063	5	49	9	15½	8¾
J½	15.717	49.375	5	49½	9½	15¾	9¼
J¾	15.816	49.688	5¼	49¾	9¾	15¾	9½
K	15.915	50	5¼	50	10	16	9¾
K¼	16.015	50.313	5½	50¼	10¼	16	10
K½	16.114	50.625	5½	50¾	10¾	16	10¼
K¾	16.214	50.938	5¾	51	11	16¼	10¾
L	16.313	51.25	5¾	51¼	11¼	16¼	11
L¼	16.413	51.563	6	51½	11½	16½	11¼
L½	16.512	51.875	6	52	12	16½	11½
L¾	16.612	52.188	6¼	52¼	12¼	16½	11¾
M	16.711	52.5	6¼	52½	12½	16¾	12¼
M¼	16.811	52.813	6¼	52¾	12¾	16¾	12½
M½	16.91	53.125	6½	53¼	13¼	17	12¾
M¾	17.01	53.438	6½	53½	13½	17	13
N	17.109	53.75	6¾	53¾	13¾	17	13¼
N¼	17.209	54.063	6¾	54	14	17¼	13¾
N½	17.308	54.375	7	54½	14½	17¼	14
N¾	17.408	54.688	7	54¾	14¾	17½	14¼
O	17.507	55	7¼	55	15	17½	14½
O¼	17.607	55.313	7¼	55¼	15¼	17½	14¾
O½	17.706	55.625	7½	55¾	15¾	17¾	15
O¾	17.805	55.938	7½	56	16	17¾	15½
P	17.905	56.25	7¾	56¼	16¼	18	15¾
P¼	18.004	56.563	7¾	56½	16½	18	16
P½	18.104	56.875	8	57	17	18	16¼
P¾	18.203	57.188	8	57¼	17¼	18¼	16½
Q	18.303	57.5	8¼	57½	17½	18¼	17
Q¼	18.402	57.813	8¼	57¾	17¾	18½	17¼
Q½	18.502	58.125	8½	58¼	18¼	18½	17½
Q¾	18.601	58.438	8½	58½	18½	18½	17¾
R	18.701	58.75	8¾	58¾	18¾	18¾	18
R¼	18.8	59.063	8¾	59	19	18¾	18½
R½	18.9	59.375	9	59½	19½	19	18¾
R¾	18.999	59.688	9	59¾	19¾	19	19
S	19.099	60	9¼	60	20	19	19¼
S¼	19.198	60.313	9¼	60¼	20¼	19¼	19½
S½	19.298	60.625	9½	60¾	20¾	19¼	20
S¾	19.397	60.938	9½	61	21	19½	20¼
T	19.496	61.25	9¾	61¼	21¼	19½	20½
T¼	19.596	61.563	9¾	61½	21½	19½	20¾
T½	19.695	61.875	10	62	22	19¾	21
T¾	19.795	62.188	10	62¼	22¼	19¾	21½
U	19.894	62.5	10¼	62½	22½	20	21¾
U¼	19.994	62.813	10¼	62¾	22¾	20	22
U½	20.093	63.125	10½	63¼	23¼	20	22¼
U¾	20.193	63.438	10½	63½	23½	20¼	22½
V	20.292	63.75	10¾	63¾	23¾	20¼	23
V¼	20.392	64.063	10¾	64	24	20½	23¼
V½	20.491	64.375	11	64½	24½	20½	23½
V¾	20.591	64.688	11	64¾	24¾	20½	23¾
W	20.69	65	11¼	65	25	20¾	24
W¼	20.79	65.313	11¼	65¼	25¼	20¾	24¼
W½	20.889	65.625	11½	65¾	25¾	21	24¾
W¾	20.989	65.938	11½	66	26	21	25
X	21.088	66.25	11¾	66¼	26¼	21	25¼
X¼	21.188	66.563	11¾	66½	26½	21¼	25½
X½	21.287	66.875	12	67	27	21¼	25¾
X¾	21.386	67.188	12	67¼	27¼	21½	26¼
Y	21.486	67.5	12¼	67½	27½	21½	26½
Y¼	21.585	67.813	12¼	67¾	27¾	21½	26¾
Y½	21.685	68.125	12¼	68¼	28¼	21¾	27
Y¾	21.784	68.438	12½	68½	28½	21¾	27¼
Z	21.884	68.75	12½	68¾	28¾	22	27¾
Z¼	21.983	69.063	12¾	69	29	22	28
Z½	22.083	69.375	12¾	69½	29½	22	28¼
Z¾	22.182	69.688	13	69¾	29¾	22¼	28½
Z+1	22.282	70	13	70	30	22¼	28¾
Z+1¼	22.381	70.313	13¼	70¼	30¼	22½	29¼
Z+1½	22.481	70.625	13¼	70¾	30¾	22½	29½
Z+1¾	22.58	70.938	13½	71	31	22½	29¾
Z+2	22.68	71.25	13½	71¼	31¼	22¾	30
Z+2¼	22.779	71.563	13¾	71½	31½	22¾	30¼
Z+2½	22.879	71.875	13¾	72	32	23	30¾
Z+2¾	22.978	72.188	14	72¼	32¼	23	31
Z+3	23.077	72.5	14	72½	32½	23	31¼
Z+3¼	23.177	72.813	14¼	72¾	32¾	23¼	31½
Z+3½	23.276	73.125	14¼	73¼	33¼	23¼	31¾
Z+3¾	23.376	73.438	14½	73½	33½	23½	32¼
Z+4	23.475	73.75	14½	73¾	33¾	23½	32½
Z+4¼	23.575	74.063	14¾	74	34	23½	32¾
Z+4½	23.674	74.375	14¾	74½	34½	23¾	33
Z+4¾	23.774	74.688	15	74¾	34¾	23¾	33¼
Z+5	23.873	75	15	75	35	23¾	33½
Z+5¼	23.973	75.313	15¼	75¼	35¼	24	34
Z+5½	24.072	75.625	15¼	75¾	35¾	24	34¼
Z+5¾	24.172	75.938	15½	76	36	24¼	34½
Z+6	24.271	76.25	15½	76¼	36¼	24¼	34¾
Z+6¼	24.371	76.563	15¾	76½	36½	24¼	35
Z+6½	24.47	76.875	15¾	77	37	24½	35½
Z+6¾	24.57	77.188	16	77¼	37¼	24½	35¾
Z+7	24.669	77.5	16	77½	37½	24¾	36

US to other sizes

US Size	Diameter	Circumference	UK	EU ISO	Italy	Russia	Japan
0	11.63	36.537		36½		11¾
0¼	11.833	37.175		37¼		11¾
0½	12.036	37.813	A¼	37¾		12
0¾	12.24	38.452	A¾	38½		12¼
1	12.443	39.09	B¼	39		12½
1¼	12.646	39.729	B¾	39¾		12¾
1½	12.849	40.367	C¼	40¼	0¼	12¾
1¾	13.052	41.005	C¾	41	1	13	1¼
2	13.256	41.644	D¼	41¾	1¾	13¼	1¾
2¼	13.459	42.282	D¾	42¼	2¼	13½	2½
2½	13.662	42.92	E¼	43	3	13¾	3
2¾	13.865	43.559	E¾	43½	3½	13¾	3½
3	14.068	44.197	F¼	44¼	4¼	14	4¼
3¼	14.272	44.836	F¾	44¾	4¾	14¼	4¾
3½	14.475	45.474	G½	45½	5½	14½	5½
3¾	14.678	46.112	H	46	6	14¾	6
4	14.881	46.751	H½	46¾	6¾	15	6¾
4¼	15.084	47.389	I	47½	7½	15	7¼
4½	15.288	48.027	I½	48	8	15¼	7¾
4¾	15.491	48.666	J	48¾	8¾	15½	8½
5	15.694	49.304	J½	49¼	9¼	15¾	9
5¼	15.897	49.943	K	50	10	16	9¾
5½	16.1	50.581	K½	50½	10½	16	10¼
5¾	16.304	51.219	L	51¼	11¼	16¼	11
6	16.507	51.858	L½	51¾	11¾	16½	11½
6¼	16.71	52.496	M	52½	12½	16¾	12¼
6½	16.913	53.134	M½	53¼	13¼	17	12¾
6¾	17.116	53.773	N	53¾	13¾	17	13¼
7	17.32	54.411	N½	54½	14½	17¼	14
7¼	17.523	55.049	O	55	15	17½	14½
7½	17.726	55.688	O½	55¾	15¾	17¾	15¼
7¾	17.929	56.326	P	56¼	16¼	18	15¾
8	18.132	56.965	P½	57	17	18¼	16½
8¼	18.336	57.603	Q	57½	17½	18¼	17
8½	18.539	58.241	Q½	58¼	18¼	18½	17½
8¾	18.742	58.88	R	59	19	18¾	18¼
9	18.945	59.518	R½	59½	19½	19	18¾
9¼	19.148	60.156	S¼	60¼	20¼	19¼	19½
9½	19.352	60.795	S¾	60¾	20¾	19¼	20
9¾	19.555	61.433	T¼	61½	21½	19½	20¾
10	19.758	62.072	T¾	62	22	19¾	21¼
10¼	19.961	62.71	U¼	62¾	22¾	20	22
10½	20.164	63.348	U¾	63¼	23¼	20¼	22½
10¾	20.368	63.987	V¼	64	24	20¼	23
11	20.571	64.625	V¾	64¾	24¾	20½	23¾
11¼	20.774	65.263	W¼	65¼	25¼	20¾	24¼
11½	20.977	65.902	W¾	66	26	21	25
11¾	21.18	66.54	X¼	66½	26½	21¼	25½
12	21.384	67.179	X¾	67¼	27¼	21½	26¼
12¼	21.587	67.817	Y¼	67¾	27¾	21½	26¾
12½	21.79	68.455	Y¾	68½	28½	21¾	27¼
12¾	21.993	69.094	Z¼	69	29	22	28
13	22.196	69.732	Z¾	69¾	29¾	22¼	28½
13¼	22.4	70.37	Z+1¼	70¼	30¼	22½	29¼
13½	22.603	71.009	Z+1¾	71	31	22½	29¾
13¾	22.806	71.647	Z+2¼	71¾	31¾	22¾	30½
14	23.009	72.286	Z+2¾	72¼	32¼	23	31
14¼	23.212	72.924	Z+3¼	73	33	23¼	31¾
14½	23.416	73.562	Z+3¾	73½	33½	23½	32¼
14¾	23.619	74.201	Z+4¼	74¼	34¼	23½	32¾
15	23.822	74.839	Z+4¾	74¾	34¾	23¾	33½
15¼	24.025	75.477	Z+5½	75½	35½	24	34
15½	24.228	76.116	Z+6	76	36	24¼	34¾
15¾	24.432	76.754	Z+6½	76¾	36¾	24½	35¼
16	24.635	77.393	Z+7	77½	37½	24¾	36