Sizelane

Should you size up for running shoes?

5 of the 11 brands below say to go up for running. Brooks, ASICS, On and Saucony count from a shoe you already wear, and Veja says most of its running styles run small. The others give general advice: 3 say to go up if your foot falls between sizes, 2 leave it to the fit you want, and HOKA says the closest size.

By Sizelane · Published 2026-11-01 · Numbers computed from the official charts on this site

What each brand says

BrandIn shortApplies toCounted fromWhat the brand says (our summary)
BrooksSize upRunning shoesYour dress shoeOrder Brooks running shoes 1/2 to one size larger than your dress shoe. Source
ASICSSize upRunning shoesYour casual shoeFor running shoes, ASICS generally recommends going up a half size from your casual shoe size. Source
OnSize upRunning shoesYour street shoeRunning shoes should be at least half a size bigger than your street shoe, with some room in the toebox. Source
SauconySize upPerformance shoesYour lifestyle shoeFor performance shoes, choose a size up from your usual lifestyle shoe size. Source
VEJASize upMost of its running stylesNot statedSeveral models carry their own advice, e.g. Salar, Rio Branco, SDU, Dekkan and most running styles run small (order one size up), while the sandals run large (order one size down). Source
NikeIf between sizesAll shoesYour measured footMeasure both feet and use the longer measurement; if the measurement falls between sizes, size up. Source
Under ArmourIf between sizesAll shoesYour measured footTrace your whole foot with full weight on it and measure heel to toe; if you fall between sizes, size up. Source
New BalanceIf between sizesAll shoesNot statedIf your feet are between sizes, choose the larger size. Source
adidasYour choiceAll shoesNot statedIf between sizes, go one size down for a tight fit or one size up for a loose fit. Source
MizunoYour choiceAll shoesNot statedIf you are between two sizes, go one size down for a tight fit or one size up for a loose fit. Source
HOKAClosest sizeAll shoesYour measured footMeasure each foot heel to longest toe, use the longer foot, and round to the closest size within 2 mm. Source

"In short" is our reading of each statement. Follow the link for the brand's wording.

Up from what?

"A half size up" means nothing without a starting point. Brooks, ASICS, On and Saucony count from a shoe you already wear, and they name different ones. HOKA, Nike and Under Armour count from a measurement. If your everyday shoe is already larger than your measured foot, the two starting points give different answers.

If you start from a measurement, Brooks has separate advice: Leave about a thumb's width between your longest toe and the tip of the shoe; consider a half size up from your measured size. Source.

A worked example

Take a foot measured at 26.4 cm. HOKA's chart lists that as men's US 9, so its closest size is 9. Half a size up moves you to 26.8 cm, which adds 4 mm. Across brands a half size is 4 to 5 mm. We have no data on how that length feels on a run; compare it with the room brands say to leave.

Converter result for HOKA US men's 9 with matching sizes in other brands
HOKA US 9 in the converter, with the same length at other brands. Open this example

When the chart cannot help

Brooks publishes US, UK and EU sizes in this chart but no length, so a measured foot cannot be matched to a Brooks size from the chart alone.

Converter result for Brooks US 9.5 showing no length column and a message explaining it
Brooks in the converter: no length column, so there is nothing to match against. Open the Brooks chart

Length is not the only variable

Altra describes room through shape: Every Altra shoe has a roomy FootShape toe box (not a wide shoe); styles come in Original (roomiest), Standard and Racing (snug midfoot) FootShape fits. Source. Width is a separate choice too: at HOKA, wide adds 8 mm of foot width at the same length.

Start from your measured foot

Sources

Size data: the source register, read with the method described here.

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