Does On run true to size?

On women's shoes, by its own chart

Chart runs long: maybe half a size down

By its own size chart, On builds each size for a foot about 0.3 cm longer than the median of 14 other brands' charts. On length alone that points you half a size down. A chart does not measure width, so if your feet are wide or you are between sizes, stay with your usual size.

Source: On size guide, checked 2026-09-17.

Convert your size to On On products and size chart

If you wear this at another brand, buy this at On

US women's sizes. Each cell reads the other brand's own chart, then finds the On size built for the same foot (or the same label, when one chart has no foot lengths).
You wear	Size 7 there	Size 8 there	Size 9 there
Nike	On 7	On 8	On 9
adidas	On 7 or 6.5	On 7.5	On 8.5
HOKA	On 7	On 8	On 9
Brooks	On 7	On 8	On 9
ASICS	On 7	On 8	On 8.5 or 9
New Balance	On 7	On 8	On 9
Saucony	On 6.5	On 7.5	On 8.5

Every size, not just these three: follow a brand name for the full On table.

Size by size: On against the other charts

The foot length On builds each US women's size for, beside the median of every other brand that publishes one. Half a US size is 0.42 cm.
US women's	On builds it for	Median brand	Difference
6	23 cm	23 cm (14 brands)	same
6.5	23.5 cm	23.5 cm (13 brands)	same
7	24 cm	24 cm (14 brands)	same
7.5	24.5 cm	24 cm (13 brands)	+0.50 cm
8	25 cm	24.5 cm (14 brands)	+0.50 cm
8.5	25.5 cm	25 cm (12 brands)	+0.50 cm
9	26 cm	25.5 cm (14 brands)	+0.50 cm
9.5	26.5 cm	26 cm (12 brands)	+0.50 cm
10	27 cm	26.5 cm (14 brands)	+0.50 cm

Tinted rows differ by half a size or more. Brands round their foot lengths, often to the half centimetre, so read the average, not a single row.

What a size chart cannot tell you

A chart gives one number per size: the foot length. Width, toe box shape, the heel and how much the upper stretches are on no chart, and they decide whether a shoe feels short. That is why people sometimes say a brand runs small when its chart says it runs long: a narrow toe box can crowd a foot the chart says fits.

If you have wide feet or sit between sizes, take the larger size, or check whether the model comes in a wide fit.

Wearer reports appear on the shoe converter once five people who own both brands have told us what fits. They rank above the charts, because charts describe a shoe and wearers describe a fit. Add a pair you own to help.