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Convert / Shoes

Under Armour to On shoe size

The short answer

Under Armour 5 is On 5.5 by the two brands' own charts. 13 of 15 Under Armour sizes land on a different label at On.

Both brands publish the foot length each size is built for, so every row matches a foot, not a label.

Every Under Armour size read across to On. US women's sizes on the left, US women's on the right.
Under ArmourUnder Armour builds it forOn, by chartSame labelOn builds it forOn also prints
5foot length 22.5 cm5.55foot length 22.5 cmUK 3.5 · EU 36.5 · CM / JP 22.5
5.5foot length 23 cm65.5foot length 23 cmUK 4 · EU 37 · CM / JP 23
6foot length 23.5 cm6.56foot length 23.5 cmUK 4.5 · EU 37.5 · CM / JP 23.5
6.5foot length 23.5 cm6.56.5foot length 23.5 cmUK 4.5 · EU 37.5 · CM / JP 23.5
7foot length 24 cm77foot length 24 cmUK 5 · EU 38 · CM / JP 24
7.5foot length 24 cm77.5foot length 24 cmUK 5 · EU 38 · CM / JP 24
8foot length 24.5 cm7.58foot length 24.5 cmUK 5.5 · EU 38.5 · CM / JP 24.5
8.5foot length 25 cm88.5foot length 25 cmUK 6 · EU 39 · CM / JP 25
9foot length 25.5 cm8.59foot length 25.5 cmUK 6.5 · EU 40 · CM / JP 25.5
9.5foot length 26 cm99.5foot length 26 cmUK 7 · EU 40.5 · CM / JP 26
10foot length 26.5 cm9.510foot length 26.5 cmUK 7.5 · EU 41 · CM / JP 26.5
10.5foot length 27 cm1010.5foot length 27 cmUK 8 · EU 42 · CM / JP 27
11foot length 27.5 cm10.511foot length 27.5 cmUK 8.5 · EU 42.5 · CM / JP 27.5
11.5foot length 28 cm11not publishedfoot length 28 cmUK 9 · EU 43 · CM / JP 28
12foot length 28.5 cm11 or 1212foot length 28 cmUK 9 · EU 43 · CM / JP 28
Tinted rows change label or sit between two sizes. Read from the two charts only; no formula and no averaging.

What wearers say

Charts describe a garment. People who own both brands describe a fit, and their answer ranks above this table once five of them stand behind it. Pick your size in the converter to see whether there are enough yet.

Open in the converterAdd an item you own

Sources

On to Under Armour