Getting the size right is the single biggest reason a pair of shoes gets worn every day instead of sitting in a closet. This guide covers how RunLife lists sizes, how to measure your foot at home in about two minutes, and how US, EU and UK numbers line up.
How RunLife lists sizes
Every pair on this store is listed in US sizing with the EU equivalent in brackets — for example US 8 (EU 41). The US number follows the men's scale, which is the scale most running brands print inside the shoe.
If you normally buy women's sizes, add roughly 1.5 to your number to get the equivalent here. A women's US 9.5 is about a men's US 8, which is the US 8 (EU 41) option.
The fastest way to know your size: measure your foot
Brand numbers drift. Foot length does not. It takes two minutes:
- Put on the socks you'd actually run in.
- Tape a sheet of paper to a hard floor against a wall.
- Stand on it with your heel touching the wall, weight on both feet.
- Have someone mark the paper at the tip of your longest toe — that isn't always the big toe.
- Measure heel mark to toe mark in centimetres or inches.
- Repeat for the other foot. Feet are rarely identical; use the longer one.
Then add 0.5 to 1 cm (about 1/4 to 3/8 in) of room for running shoes. Your foot lengthens and swells over a run, and a toe pressed against the front is how people lose toenails on long runs.
Conversion table
| Foot length | US (men's) | EU | UK | US (women's) |
|---|---|---|---|---|
| 23.3 cm / 9.2 in | 5 | 37 | 4.5 | 6.5 |
| 24.0 cm / 9.4 in | 6 | 38 | 5.5 | 7.5 |
| 24.7 cm / 9.7 in | 6.5 | 39 | 6 | 8 |
| 25.3 cm / 10.0 in | 7 | 40 | 6.5 | 8.5 |
| 26.0 cm / 10.2 in | 8 | 41 | 7.5 | 9.5 |
| 26.7 cm / 10.5 in | 8.5 | 42 | 8 | 10 |
| 27.3 cm / 10.7 in | 9.5 | 43 | 9 | 11 |
| 28.0 cm / 11.0 in | 10 | 44 | 9.5 | 11.5 |
Read the table by foot length first, then take the US column. That is the number to pick on the product page.
What changes between brands
Length is fairly consistent across brands. Width and shape are not, and that is what people actually feel.
- HOKA and New Balance tend to run roomy through the toe box.
- ASICS and Nike performance models often feel narrower, especially the racing-oriented ones.
- On sits in between, with a snug midfoot.
- Salomon trail shoes are built to lock the foot down and feel tighter by design.
If you're between two sizes, size up rather than down. A slightly long shoe can be tuned with lacing and a thicker sock. A short one cannot be fixed.
When to size up half a size
- You're buying for long runs or marathon training.
- Your feet swell noticeably in heat or late in the day.
- You have wide feet — see our guide to running shoes for wide feet.
- You wear thick or cushioned socks.
Frequently asked
Is EU sizing the same everywhere in Europe?
Broadly yes for the numbers, but the underlying French point system means half sizes are inconsistent between brands. Foot length is still the safer anchor.
Should I measure in the morning or evening?
Evening, or right after a walk. Feet are at their largest then, and that's the size you want the shoe to fit.
What if the size is wrong when it arrives?
You have 30 days to change your mind, and you never ship anything back. Email contact@shoprunlife.com and we'll sort it out.
Ready to pick a pair? Start with the running collection or browse best sellers.