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Convert / Shoes

On to ASICS shoe size

The short answer

On 5 is ASICS 4.5 by the two brands' own charts. 8 of 14 On sizes land on a different label at ASICS.

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

On 1 sizes the charts land two or more sizes from the same label. Brands do not measure the body the same way, so on those rows treat the chart answer and the same label as the two ends of a range.

Every On size read across to ASICS. US women's sizes on the left, US women's on the right.
OnOn builds it forASICS, by chartSame labelASICS builds it forASICS also prints
5foot length 22 cm4.55foot length 22 cmUK 2.5 · EU 35
5.5foot length 22.5 cm55.5foot length 22.5 cmUK 3 · EU 35.5
6foot length 23 cm66foot length 23 cmUK 4 · EU 37
6.5foot length 23.5 cm6.56.5foot length 23.5 cmUK 4.5 · EU 37.5
7foot length 24 cm77foot length 24 cmUK 5 · EU 38
7.5foot length 24.5 cm7.57.5foot length 24.5 cmUK 5.5 · EU 39
8foot length 25 cm88foot length 25 cmUK 6 · EU 39.5
8.5foot length 25.5 cm8.58.5foot length 25.5 cmUK 6.5 · EU 40
9foot length 26 cm9.59foot length 26 cmUK 7.5 · EU 41.5
9.5foot length 26.5 cm109.5foot length 26.5 cmUK 8 · EU 42
10foot length 27 cm10.510foot length 27 cmUK 8.5 · EU 42.5
10.5foot length 27.5 cm1110.5foot length 27.5 cmUK 9 · EU 43.5
11foot length 28 cm11.511foot length 28 cmUK 9.5 · EU 44
12foot length 29 cm1312foot length 29 cmUK 11 · EU 46
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

ASICS to On