Every Altra conversion below is verified against the brand's official size chart.
Altra fit — the short version
The FootShape toebox adds width and toe splay, not length — keep your regular running-shoe size and do not size down. Lone Peak and Olympus fit true; the Escalante trimmed some volume but still fits true. The whole line is zero drop, so ease in over a few weeks if you are new to Altra.
Men's size conversions
US 7 — women's US 8.5, UK 6, EU 40, Japan 25 cm
US 7.5 — women's US 9, UK 6.5, EU 40.5, Japan 25.5 cm
US 8 — women's US 9.5, UK 7, EU 41, Japan 26 cm
US 8.5 — women's US 10, UK 7.5, EU 42, Japan 26.5 cm
US 9 — women's US 10.5, UK 8, EU 42.5, Japan 27 cm
US 9.5 — women's US 11, UK 8.5, EU 43, Japan 27.5 cm
US 10 — women's US 11.5, UK 9, EU 44, Japan 28 cm
US 10.5 — women's US 12, UK 9.5, EU 44.5, Japan 28.5 cm
US 11 — women's US 12.5, UK 10, EU 45, Japan 29 cm
US 11.5 — women's US 13, UK 10.5, EU 46, Japan 29.5 cm
US 12 — women's US 13.5, UK 11, EU 46.5, Japan 30 cm
US 12.5 — women's US 14, UK 11.5, EU 47, Japan 30.5 cm
US 13 — women's US 14.5, UK 12, EU 48, Japan 31 cm
Women's size conversions
US 5.5 — men's US 4, UK 3.5, EU 36, Japan 22 cm
US 6 — men's US 4.5, UK 4, EU 37, Japan 22.5 cm
US 6.5 — men's US 5, UK 4.5, EU 37.5, Japan 23 cm
US 7 — men's US 5.5, UK 5, EU 38.5, Japan 23.5 cm
US 7.5 — men's US 6, UK 5.5, EU 38.5, Japan 24 cm
US 8 — men's US 6.5, UK 6, EU 39, Japan 24.5 cm
US 8.5 — men's US 7, UK 6.5, EU 40, Japan 25 cm
US 9 — men's US 7.5, UK 7, EU 40.5, Japan 25.5 cm
US 9.5 — men's US 8, UK 7.5, EU 41, Japan 26 cm
US 10 — men's US 8.5, UK 8, EU 42, Japan 26.5 cm
US 10.5 — men's US 9, UK 8.5, EU 42.5, Japan 27 cm
US 11 — men's US 9.5, UK 9, EU 43, Japan 27.5 cm
US 12 — men's US 10.5, UK 10, EU 44.5, Japan 28.5 cm
If you normally wear another brand
Anchored on your ASICS size:
- Asics: Baseline — true to size. One of the roomier toeboxes in running; wide widths on core models.
- On: Same size. Narrow-to-medium fit; go up half in waterproof models.
- HOKA: Half size up. Runs about a half size short of Asics, with a snug, tapered toebox.
- Adidas: Same size; half up for wide feet. Race lines run long and narrow.
- Salomon: Half size up in Speedcross. European last — narrow and precise; Sense Ride fits truer.
- norda: Half size up in 001 and 005; full size up in 002 and 003. The brand's own guidance — follow it.
Common questions
Does Altra run true to size? Yes — keep your regular running-shoe size. The FootShape toebox adds width and toe splay, not length, so do not size down. Lone Peak and Olympus fit true, and the Escalante still fits true.
Is Altra zero drop? Yes — the whole line is zero drop, so ease in over a few weeks if you are new to Altra.
You will also find these charts on every Altra product page on enroute.run, right beside the shoe you are looking at.