Nike, Adidas, New Balance, ASICS: Complete Size Comparison Chart
A US 10 in Nike is not the same as a US 10 in New Balance. Every brand uses slightly different lasts (the foot-shaped mould they build around), which means the actual internal length in centimetres varies from brand to brand.
This chart gives you the real measurements so you can cross-shop between brands without guessing.
The Size Comparison Chart (Men's, in cm)
These measurements represent the internal foot length each brand targets for that US size. Your foot should be slightly shorter than the number listed (you want 0.5 to 1cm of toe room).
| US Size | Nike (cm) | Adidas (cm) | New Balance (cm) | ASICS (cm) | Converse (cm) |
|---|---|---|---|---|---|
| 7 | 25.0 | 25.5 | 25.0 | 25.0 | 25.5 |
| 7.5 | 25.5 | 25.5 | 25.5 | 25.5 | 26.0 |
| 8 | 26.0 | 26.5 | 26.0 | 26.0 | 26.5 |
| 8.5 | 26.5 | 26.5 | 26.5 | 26.5 | 27.0 |
| 9 | 27.0 | 27.0 | 27.0 | 27.0 | 27.5 |
| 9.5 | 27.5 | 27.5 | 27.5 | 27.5 | 28.0 |
| 10 | 28.0 | 28.0 | 28.0 | 28.0 | 28.5 |
| 10.5 | 28.5 | 28.5 | 28.5 | 28.5 | 29.0 |
| 11 | 29.0 | 29.0 | 29.0 | 29.0 | 29.5 |
| 11.5 | 29.5 | 29.5 | 29.5 | 29.5 | 30.0 |
| 12 | 30.0 | 30.0 | 30.0 | 30.0 | 30.5 |
| 12.5 | 30.5 | 30.5 | 30.5 | 30.5 | 31.0 |
| 13 | 31.0 | 31.0 | 31.0 | 31.0 | 31.5 |
Quick rule: If a brand "runs small," it means the shoe feels shorter or tighter than the cm measurement suggests. The number on the box might match, but the fit tells a different story.
Brand-by-Brand Breakdown
Nike - Runs Narrow and Slightly Short
Nike is the brand most people need to size up in. Their lasts tend to run about half a size small, and the toe box is on the narrow side. If you're between sizes, always go up.
This is especially true for models like the Air Force 1 (notoriously tight when new) and the Pegasus (snug in the midfoot). The Dunk runs closer to true to size, but the leather versions take a few wears to break in.
The move: Go up half a size from your measured foot length. If you have wide feet, Nike is probably not your brand unless you specifically buy their wide options (which are limited).
Adidas - True to Size for Most People
Adidas is the most consistent brand in the chart. A US 10 feels like a US 10. The Ultraboost has a stretchy Primeknit upper that gives a little extra room, while the Samba and Gazelle run slightly narrower because of the leather construction.
The Stan Smith is reliable for true-to-size fit. The Superstar has a wider toe box than most Adidas shoes, so some people actually size down half a size in those.
The move: Stick with your measured size. If you're buying a knit shoe (Ultraboost, NMD), you might even go down half a size for a snugger fit.
New Balance - Runs Wide (Great for Wider Feet)
New Balance is the go-to for people who find Nike and Adidas too narrow. Their standard D width is already wider than most brands' regular fit. And they actually offer 2E (wide) and 4E (extra wide) in most of their popular models.
The 990v6 and 574 are known for generous fits. The 550 is a bit narrower since it's a retro basketball shoe, but still more forgiving than a Nike Dunk.
The move: True to size for length. If you have narrow feet, New Balance might feel a bit roomy. Try their B width (narrow) options if you want a tighter fit.
ASICS - True to Size, but Narrow in Some Models
ASICS runs true to size for length. The catch is width. Models like the Gel-Kayano and GT-2000 have a narrower fit through the midfoot, which is great for stability but uncomfortable for wide-footed runners.
The Gel-Nimbus is more forgiving width-wise. The Japan S (lifestyle shoe) runs true and has a decent toe box.
The move: Stick with your measured size. If you have wide feet and want ASICS for running, look for their wide (2E) options in the Nimbus or GT-2000 lines.
Converse - Runs a Full Size Large
Converse is the outlier. The Chuck Taylor has run big since the 1960s and they have never fixed it. If you wear a US 10 in Nike, you probably need a US 9 in Converse. Some people even go down 1.5 sizes.
The Chuck 70 fits slightly differently than the regular Chuck Taylor All Star. The 70 has more cushioning and a slightly different shape, but still runs about a full size large.
The move: Size down a full size. If you're a half size (like US 9.5), round down to US 8.5 or even US 8 in Chucks.
Tips for Buying Online Without Trying On
Measure your feet first. Not your old shoe size from memory. Actually measure your feet in cm, then match to the chart above. Feet change shape over time.
Read reviews for fit, not just quality. Sort by "most recent" and look for comments about sizing. If 30% of reviewers say "runs small," believe them.
Check the return policy before you buy. Any retailer worth buying from offers free returns on unworn shoes. Don't risk it with a no-returns store.
Order two sizes if you're unsure. Buy your measured size and half a size up. Return the one that doesn't fit. It takes 5 extra minutes and saves you weeks of exchange shipping.
Know your foot width. Length gets all the attention, but width is where most bad fits happen. If your pinky toe is getting crushed, the shoe is too narrow, not too short. Check our guide on the best brands for wide feet.
Bottom line: Don't trust the number on the box. A US 10 means something different in every brand. Use cm measurements, know your foot width, and always check brand-specific fit notes before buying.