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adidas UltraBoost 21 'Core Black'

Name: adidas UltraBoost 21 'Core Black'
Brand: adidas
SKU: FY0378
Availability: InStock

adidas · Style FY0378 · Released 2021-01-29

from $197.30

Select a size:

Size chart — adidas

Full adidas size guide

Use the chart below to convert between US, UK, EU and JP sizes.

Men

US	UK	EU	JP (cm)
4	3.5	36	22.1
4.5	4	36 2/3	22.5
5	4.5	37 1/3	22.9
5.5	5	38	23.3
6	5.5	38 2/3	23.8
6.5	6	39 1/3	24.2
7	6.5	40	24.6
7.5	7	40 2/3	25.0
8	7.5	41 1/3	25.5
8.5	8	42	25.9
9	8.5	42 2/3	26.3
9.5	9	43 1/3	26.7
10	9.5	44	27.1
10.5	10	44 2/3	27.6
11	10.5	45 1/3	28.0
11.5	11	46	28.4
12	11.5	46 2/3	28.8
12.5	12	47 1/3	29.3
13	12.5	48	29.7
13.5	13	48 2/3	30.1
14	13.5	49 1/3	30.5
14.5	14	50	31.0
15	14.5	50 2/3	31.4
16	15	51 1/3	31.8
17	16	52 2/3	32.6
18	17	53 1/3	33.5
19	18	54 2/3	34.3
20	19	55 2/3	35.2

Women

US	UK	EU	JP (cm)
5	3.5	36	22.1
5.5	4	36 2/3	22.5
6	4.5	37 1/3	22.9
6.5	5	38	23.3
7	5.5	38 2/3	23.8
7.5	6	39 1/3	24.2
8	6.5	40	24.6
8.5	7	40 2/3	25.0
9	7.5	41 1/3	25.5
9.5	8	42	25.9
10	8.5	42 2/3	26.3
10.5	9	43 1/3	26.7
11	9.5	44	27.1
11.5	10	44 2/3	27.6
12	10.5	45 1/3	28.0
12.5	11	46	28.4
13	11.5	46 2/3	28.8
13.5	12	47 1/3	29.3
14	12.5	48	29.7
14.5	13	48 2/3	30.1
15	13.5	49 1/3	30.5
15.5	14	50	31.0

Kids

US	UK	EU	JP (cm)
1k	0k	16	8.1
2k	1k	17	9.0
3k	2k	18	9.8
4k	3k	19	10.6
5k	4k	20	11.5
5.5k	5k	21	12.3
6k	5.5k	22	12.8
6.5k	6k	23	13.2
7k	6.5k	23.5	13.6
7.5k	7k	24	14.0
8k	7.5k	25	14.5
8.5k	8k	25.5	14.9
9k	8.5k	26	15.3
9.5k	9k	26.5	15.7
10k	9.5k	27	16.1
10.5k	10k	28	16.6
11k	10.5k	28.5	17.0
11.5k	11k	29	17.4
12k	11.5k	30	17.8
12.5k	12k	30.5	18.3
13k	12.5k	31	18.7
13.5k	13k	31.5	19.1
1	13.5k	32	19.5
1.5	1	33	20.0
2	1.5	33.5	20.4
2.5	2	34	20.8
3	2.5	35	21.2
3.5	3	35.5	21.6
4	3.5	36	22.1
4.5	4	36 2/3	22.5
5	4.5	37 1/3	22.9
5.5	5	38	23.3
6	5.5	38 2/3	23.8
6.5	6	39 1/3	24.2
7	6.5	40	24.6
7.5	7	40 2/3	25.0

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Size, price & UPC details

Size	Price	UPC	Delivery
US M 4 / W 5	$200.60	194813169228	3-4 business days
US M 4.5 / W 5.5	$197.30	194813165565	3-4 business days
US M 5 / W 6	—	194813169211	Out of stock
US M 5.5 / W 6.5	$229.20	194813165589	3-4 business days
US M 6 / W 7	—	194813165435	Out of stock
US M 6.5 / W 7.5	—	194813165572	Out of stock
US M 7 / W 8	—	194813165558	Out of stock
US M 7.5 / W 8.5	—	194813165527	Out of stock
US M 8 / W 9	—	194813165503	Out of stock
US M 8.5 / W 9.5	$212.43	194813165510	5-7 business days
US M 9 / W 10	—	194813165466	Out of stock
US M 9.5 / W 10.5	—	194813165534	Out of stock
US M 10 / W 11	—	194813165459	Out of stock
US M 10.5 / W 11.5	—	194816368369	Out of stock
US M 11 / W 12	$238.55	194813165497	5-7 business days
US M 11.5 / W 12.5	$222.60	194813165541	3-4 business days
US M 12 / W 13	$251.20	194813169204	3-4 business days
US M 12.5 / W 13.5	—	194813165473	Out of stock
US M 13 / W 14	—	194813165480	Out of stock
US M 13.5 / W 14.5	—	194811760267	Out of stock
US M 14 / W 15	—	194813165442	Out of stock
US M 14.5 / W 15.5	—	194811760250	Out of stock
US M 15 / W 16	—	194813165596	Out of stock
US M 16 / W 17	—	194819545170	Out of stock
US M 17 / W 18	—	194819545163	Out of stock
US M 18 / W 19	—	194819545156	Out of stock

About the adidas UltraBoost 21 'Core Black'

The adidas UltraBoost 21 ‘Core Black’ applies a rudimentary palette to a performance running shoe that combines lightweight comfort with enhanced energy return. Recycled Primeblue materials, including Parley Ocean Plastic, goes into the construction of the knit upper, fortified with a midfoot cage and molded heel counte. An optimized Boost midsole, made with 6% more Boost capsules than the UltraBoost 20, features added responsiveness via a new Torsion system that adidas calls Linear Energy Push.