Japanese Ring Size Guide

NIWAKA jewelry uses Japanese ring sizes. Ring Sizing Kits and a ring size comparison chart are available below to help you determine your Japanese ring size.

Ring Sizing Kit

Japanese Ring Sizing Chart

Some Points to Keep in Mind About Sizes

Measuring Ring Size for Wider Designs

Because the wedding ring designs listed below are wider than other designs, the ring itself may fit tighter than the ring gauge. As such, some customers prefer a size that is 0.5 or 1.0 larger than the ring size measured.

Half Sizes

Although your Ring Sizing Kit measures sizes in one-size increments, rings can be made in 0.5 increments (excluding eternity-style rings, which are made in one-size increments.)

Resizing

Within 30 days of receipt of your ring, you can apply for our complimentary resizing service. For designs that cannot be resized, we can provide you with a new ring made to the adjusted size at no additional charge. For more detailed information regarding resizing, please see the After-Sales Services page.

Please keep in mind that available ring sizes and resizing range vary by design. For information regarding available sizes and resizing range for a particular design, please see the corresponding design page.

Ring Sizing Kit

Ring Sizing Kits can be purchased to measure your Japanese ring size. This kit measures sizes 1-30 on the Japanese scale in one-size increments.

If you purchase a ring after purchasing a Ring Sizing Kit, the price of the kit will be deducted from the price of the ring.

Applying Your Ring Sizing Kit Price Discount

After purchasing a Ring Sizing Kit, you will receive a confirmation email containing a coupon code that can be used later to obtain a corresponding price discount. To receive your price discount, enter the code in the Coupon Code box during checkout when you purchase your ring.

About Coupon Codes

Each Ring Sizing Kit coupon code is valid for one ring purchase only. For any one purchase, only one coupon code may be used. If you have more than one coupon code, each code must be applied to a separate purchase.

USING YOUR RING SIZING KIT

RING SIZING KIT

Japanese ring sizes 1-30
Material: Plastic

Price: $5

Shipping Date:
approximately 3 to 5 business days after payment confirmation

Japanese Ring Sizing Chart

The chart below shows the corresponding measurements for ring sizes on the US and Japanese scale. If you know your US ring size or ring measurements in inches or millimeters, you can use that information to determine the nearest Japanese ring size.

Japanese Scale	US Scale	Inner Circumference		Diameter
(JCS)		(mm)	(inches)	(mm)	(inches)
	1	39.10	1.54	12.45	0.49
	1 1/2	40.38	1.59	12.85	0.51
1		40.84	1.61	13.00	0.51
1.5		41.36	1.63	13.17	0.52
	2	41.65	1.64	13.26	0.52
2		41.89	1.65	13.33	0.52
2.5		42.41	1.67	13.50	0.53
	2 1/2	42.93	1.69	13.67	0.54
3		42.94	1.69	13.67	0.54
3.5		43.46	1.71	13.83	0.54
4		43.98	1.73	14.00	0.55
	3	44.21	1.74	14.07	0.55
4.5		44.51	1.75	14.17	0.56
5		45.03	1.77	14.33	0.56
	3 1/2	45.48	1.79	14.48	0.57
5.5		45.55	1.79	14.50	0.57
6		46.08	1.81	14.67	0.58
6.5		46.60	1.83	14.83	0.58
	4	46.76	1.84	14.88	0.59
7		47.12	1.86	15.00	0.59
7.5		47.65	1.88	15.17	0.60
	4 1/2	48.04	1.89	15.29	0.60
8		48.17	1.90	15.33	0.60
8.5		48.69	1.92	15.50	0.61
9		49.22	1.94	15.67	0.62
	5	49.31	1.94	15.70	0.62
9.5		49.74	1.96	15.83	0.62
10		50.27	1.98	16.00	0.63
	5 1/2	50.59	1.99	16.10	0.63
10.5		50.79	2.00	16.17	0.64
11		51.31	2.02	16.33	0.64
11.5		51.84	2.04	16.50	0.65
	6	51.87	2.04	16.51	0.65
12		52.36	2.06	16.67	0.66
12.5		52.88	2.08	16.83	0.66
	6 1/2	53.14	2.09	16.92	0.67
13		53.41	2.10	17.00	0.67
13.5		53.93	2.12	17.17	0.68
	7	54.42	2.14	17.32	0.68
14		54.45	2.14	17.33	0.68
14.5		54.98	2.16	17.50	0.69
15		55.50	2.19	17.67	0.70
	7 1/2	55.70	2.19	17.73	0.70
15.5		56.03	2.21	17.83	0.70
16		56.55	2.23	18.00	0.71
	8	56.97	2.24	18.14	0.71
16.5		57.07	2.25	18.17	0.72
17		57.60	2.27	18.33	0.72
17.5		58.12	2.29	18.50	0.73
	8 1/2	58.25	2.29	18.54	0.73
18		58.64	2.31	18.67	0.73
18.5		59.17	2.33	18.83	0.74
	9	59.53	2.34	18.95	0.75
19		59.69	2.35	19.00	0.75
19.5		60.21	2.37	19.17	0.75
20		60.74	2.39	19.33	0.76
	9 1/2	60.80	2.39	19.35	0.76
20.5		61.26	2.41	19.50	0.77
21		61.78	2.43	19.67	0.77
	10	62.08	2.44	19.76	0.78
21.5		62.31	2.45	19.83	0.78
22		62.83	2.47	20.00	0.79
22.5		63.36	2.49	20.17	0.79
	10 1/2	63.36	2.49	20.17	0.79
23		63.88	2.51	20.33	0.80
23.5		64.40	2.54	20.50	0.81
	11	64.64	2.54	20.57	0.81
24		64.93	2.56	20.67	0.81
24.5		65.45	2.58	20.83	0.82
	11 1/2	65.91	2.59	20.98	0.83
25		65.97	2.60	21.00	0.83
25.5		66.50	2.62	21.17	0.83
26		67.02	2.64	21.33	0.84
	12	67.19	2.65	21.39	0.84
26.5		67.54	2.66	21.50	0.85
27		68.07	2.68	21.67	0.85
	12 1/2	68.47	2.70	21.79	0.86
27.5		68.59	2.70	21.83	0.86
28		69.11	2.72	22.00	0.87
28.5		69.64	2.74	22.17	0.87
	13	69.74	2.75	22.20	0.87
29		70.16	2.76	22.33	0.88
29.5		70.69	2.78	22.50	0.89
	13 1/2	71.02	2.80	22.61	0.89
30		71.21	2.80	22.67	0.89

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