Sizing Showdown: Nike vs. Adidas Sneakers, Which Brand Runs Bigger?
Nike and Adidas are the two most popular sneaker brands on the planet, but their sizing is not interchangeable. This data-backed guide tells you exactly how to convert between them so you never buy the wrong size again.
Sizing at a glance
Nike runs true to size for footwear. Apparel varies, performance and compression pieces run small, lifestyle and fleece pieces are true to size. When in doubt on apparel, size up one.
True to size; running shoes run slightly small
Get your exact size in Nike & Adidas, based on your real measurements, not generic charts.
Build My Fit ProfileThe Verdict
Nike runs approximately half a size smaller than Adidas for most sneaker models. If you wear a US 10 in Adidas, you will likely need a US 10.5 in Nike. However, this varies significantly by model, some Nike silhouettes run true to size, and some Adidas models run small.
Use our Nike vs Adidas comparison page to see a full side-by-side breakdown.
Nike Sizing Explained
Nike sizing is famously inconsistent across product lines. The general rule is:
Nike uses a narrower last (the internal mold) for most of its performance shoes, which causes the half-size-small effect, your foot fits in length but feels compressed width-wise.
Nike Width Note
Nike running shoes are built on a D (medium) width last by default. If you have a wide foot, this is a significant issue. Nike does offer some 2E (wide) options in select running models, but the retail selection is limited.
Adidas Sizing Explained
Adidas is generally more consistent than Nike. The brand uses a slightly wider last across its range, which gives most people more wiggle room (literally).
The Adidas Ultraboost is a notable exception: the knit upper stretches with wear, so many runners find they can go true to size or even half a size down after break-in.
Size Conversion Table
| Adidas Size (US) | Nike Equivalent |
|---|---|
| 7 | 7–7.5 |
| 8 | 8–8.5 |
| 9 | 9–9.5 |
| 10 | 10–10.5 |
| 11 | 11–11.5 |
| 12 | 12 |
Stop guessing. Build your profile once and never check a size chart again.
Your fit profile knows your exact fit in every brand we cover.
Get My Sizes FreeSizing by Popular Model
Nike Air Force 1
True to size for most people. The leather upper has minimal stretch, so if you are between sizes, go up half a size for comfort.
Nike Air Max 270
Half a size small. The mesh upper is snug. Most people need to go up half a size from their usual Nike size.
Adidas Stan Smith
True to size. The leather upper stretches slightly with wear. If you have a wide foot, go up half a size.
Adidas Ultraboost
Half a size large. The Primeknit upper is very stretchy. Most runners go true to size or even half a size down after reading reviews.
Adidas Yeezy 350 V2
Runs very small, size up a full size. This is one of the most commonly mis-sized shoes in sneakers.
Bottom Line
If you are switching from Adidas to Nike, size up half a size. If switching from Nike to Adidas, you can usually go true to size or half a size down. Always check model-specific reviews, these two brands have more sizing variation within their own range than between each other.
Want the definitive side-by-side? See our full Nike vs Adidas size comparison.
Stop guessing. Build your profile once.
Never check a size chart again. Your fit profile knows your exact size across every brand we cover.
Build My Fit Profile, Free