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Nike ACG Ultrafly Trail 'Baltic Blue'

Name: Nike ACG Ultrafly Trail 'Baltic Blue'
Brand: Nike
SKU: HF5668-400
Availability: InStock

Nike · Style HF5668-400 · Released 2026-04-01

from $231.40

Select a size:

Size chart — Nike

Full Nike size guide

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

Men

US	UK	EU	JP (cm)
3.5	3	35.5	22.5
4	3.5	36	23
4.5	4	36.5	23.5
5	4.5	37.5	23.5
5.5	5	38	24
6	5.5	38.5	24
6.5	6	39	24.5
7	6	40	25
7.5	6.5	40.5	25.5
8	7	41	26
8.5	7.5	42	26.5
9	8	42.5	27
9.5	8.5	43	27.5
10	9	44	28
10.5	9.5	44.5	28.5
11	10	45	29
11.5	10.5	45.5	29.5
12	11	46	30
12.5	11.5	47	30.5
13	12	47.5	31
13.5	12.5	48	31.5
14	13	48.5	32
14.5	13.5	49	32.5
15	14	49.5	33
15.5	14.5	50	33.5
16	15	50.5	34
16.5	15.5	51	34.5
17	16	51.5	35
17.5	16.5	52	35.5
18	17	52.5	36
18.5	17.5	53	36.5
19	18	53.5	37
19.5	18.5	54	37.5
20	19	54.5	38
20.5	19.5	55	38.5
21	20	55.5	39
21.5	20.5	56	39.5
22	21	56.5	40

Women

US	UK	EU	JP (cm)
3.5	1.5	33.5	21
4	1.5	34.5	21
4.5	2	35	21.5
5	2.5	35.5	22
5.5	3	36	22.5
6	3.5	36.5	23
6.5	4	37.5	23.5
7	4.5	38	24
7.5	5	38.5	24.5
8	5.5	39	25
8.5	6	40	25.5
9	6.5	40.5	26
9.5	7	41	26.5
10	7.5	42	27
10.5	8	42.5	27.5
11	8.5	43	28
11.5	9	44	28.5
12	9.5	44.5	29
12.5	10	45	29.5
13	10.5	45.5	30
13.5	11	46	30.5
14	11.5	47	31
14.5	12	47.5	31.5
15	12.5	48	32
15.5	13	48.5	32.5
16	13.5	49	33
16.5	14	50	33.5
17	14.5	50.5	34
17.5	15	51	34.5
18	15.5	51.5	35
18.5	16	52	35.5
19	16.5	52.5	36
19.5	17	53	36.5
20	17.5	53.5	37
20.5	18	54	37.5
21	18.5	54.5	38
21.5	19	55	38.5
22	19.5	55.5	39
22.5	20	56	39.5

Kids

US	UK	EU	JP (cm)
1C	0.5	16	7
2C	1.5	17	8
3C	2.5	18.5	9
4C	3.5	19.5	10
5C	4.5	21	11
6C	5.5	22	12
7C	6.5	23.5	13
8C	7.5	25	14
9C	8.5	26	15
10C	9.5	27	16
11C	10.5	28	17
12C	11.5	29.5	18
13C	12.5	31	19
1Y	13.5	32	20
1.5Y	1	33	20.5
2Y	1.5	33.5	21
2.5Y	2	34	21.5
3Y	2.5	35	22
3.5Y	3	35.5	22.5
4Y	3.5	36	23
4.5Y	4	36.5	23.5
5Y	4.5	37.5	23.5
5.5Y	5	38	24
6Y	5.5	38.5	24
6.5Y	6	39	24.5
7Y	6	40	25

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Size, price & UPC details

Size	Price	UPC	Delivery
US M 3.5 / W 5	$255.57	198729784988	5-7 business days
US M 4 / W 5.5	$255.57	198729809063	5-7 business days
US M 4.5 / W 6	$255.57	198729870551	5-7 business days
US M 5 / W 6.5	—	198729865557	Out of stock
US M 5.5 / W 7	$326.00	198729736642	5-7 business days
US M 6 / W 7.5	—	198729786869	Out of stock
US M 6.5 / W 8	$326.00	198729766151	5-7 business days
US M 7 / W 8.5	$326.00	198729817259	5-7 business days
US M 7.5 / W 9	$326.00	198729816870	5-7 business days
US M 8 / W 9.5	$231.40	198729810540	5-7 business days
US M 8.5 / W 10	$231.40	198729631275	5-7 business days
US M 9 / W 10.5	$231.40	198729866639	5-7 business days
US M 9.5 / W 11	$231.40	198729860927	5-7 business days
US M 10 / W 11.5	$231.40	198729849137	5-7 business days
US M 10.5 / W 12	$231.40	198729781086	5-7 business days
US M 11 / W 12.5	$231.40	198729641991	5-7 business days
US M 11.5 / W 13	$231.40	198729566546	5-7 business days
US M 12 / W 13.5	$231.40	198729762535	5-7 business days
US M 12.5 / W 14	—	198729771933	Out of stock
US M 13 / W 14.5	$231.40	198729848420	5-7 business days
US M 14 / W 15.5	—	198729883636	Out of stock
US M 15 / W 16.5	$255.57	198729820839	5-7 business days

About the Nike ACG Ultrafly Trail 'Baltic Blue'

The Nike ACG Ultrafly Trail 'Baltic Blue' outfits the performance trail running shoe in a vibrant tonal design. Flowing lines adorn the electric blue mesh upper, accented with an oversized Swoosh on the lateral side and ACG branding on the back heel. The lightweight build is mounted on a matching blue ZoomX foam midsole, featuring a full-length carbon fiber plate for enhanced stability and energy return. Underfoot, the Vibram Megagrip rubber outsole is studded with strategically placed lugs for dependable grip on uneven terrain.