Do Nike Running Shoes Run Small? Nike Sizing Guide (2026)

Short answer: most Nike running shoes run true to size in length. Keep your usual US size in the Pegasus 42, Vomero 18 or Vaporfly 4. The fit is often snug through the midfoot, though, and two models run slightly small (Structure 26, Alphafly 3). If you size from a foot measurement, use Nike’s foot length chart, not the cm number on the label.

Why people say Nike runs small

The “Nike runs small” reputation comes from three things, and only one is about length.

•             A snug midfoot. Recent Pegasus, Vomero and Structure models hold the middle of the foot tightly. High-volume feet read that pressure as “too small”, even when the length is right.

•             Some models are shorter. Runner feedback rates the Structure 26 and the Alphafly 3 as slightly small, unlike the Pegasus or the Vomero.

•             The label cm is not your foot length. The box and tongue of a men’s US 9 say 27 cm. Nike’s own chart pairs that US 9 with a 10 5/16 in (26.2 cm) foot, and Nike states that the label cm differs from foot length.

The good news: the Pegasus 42 and the Pegasus Plus 2 use updated lasts with more room in the toe box than the previous versions.

Nike size chart

Foot length is your bare foot, measured the Nike way.

Men

Women

Nike’s advice when you fall between two sizes: size up.

Wearing another brand today? The StrideMatch size converter turns your current size into your Nike size. Compare with Hoka sizing and On sizing.

Model by model

The Invincible no longer appears in Nike’s current running lineup. For maximum cushioning, look at the Vomero Plus. Torn between two daily trainers? Read Nike Pegasus 42 vs ASICS Novablast 6 or Hoka Clifton 11 vs Nike Pegasus Plus 2.

What if you have wide feet?

Nike makes wide versions of the Pegasus 42, Vomero 18, Vomero Plus and Structure 26, for men and women. Race shoes (Vaporfly, Alphafly) come in standard width only.

If your foot spills over the insole when you stand on it, go wide rather than sizing up. A shoe that is too long lets your foot slide and causes heel blisters.

Get it right in 2 minutes

1.          Easiest: check the US size of your current running shoe. In the Pegasus and Vomero, keep it.

2.          Otherwise, measure your foot in the evening, standing, heel against a wall, on a sheet of paper. Keep the longer foot.

3.          Find it in the foot length column above, not the cm on the label. Between two sizes, size up.

4.          Structure 26 or Alphafly: add a half size if you are borderline.

5.          Once laced, leave about a thumb’s width in front of your longest toe.

Go further: what size running shoes should you get, our full guide.

FAQ

Do Nike run smaller than ASICS or Hoka? Not in US sizes: a US 9 is a US 9. Differences come from the EU number and from Nike’s snugger midfoot.

Should I size up in Nike running shoes? Not by default. Do it for the Structure 26 and Alphafly 3, if you are between sizes, or if you are training for a marathon.

Why does the label say 27 cm when my foot is 26 cm? The label cm is not foot length. Nike pairs a men’s US 9 (27 cm on the label) with a foot of about 10 5/16 in, or 26.2 cm. The room is built in.

Does Nike make wide running shoes? Yes: the Pegasus 42, Vomero 18, Vomero Plus and Structure 26 come in wide.

The right size starts with the right model. Take the free StrideMatch test to find which Nike matches your stride, or compare two models side by side.