Adidas Ultraboost 23 vs Nike Air Max 90 Sizing
Adidas Ultraboost 23 vs Nike Air Max 90: side-by-side fit, toe-box width and the exact size to order in each — Nike Air Max 90 runs bigger. Free interactive sizing comparison.
Should you size down from the Adidas Ultraboost 23 to the Nike Air Max 90?
Yes — size down a half size. If you wear a US 10 in the Ultraboost 23, order about a US 9.5 in the Air Max 90.
How they compare
Adidas Ultraboost 23 → Nike Air Max 90: The Adidas Ultraboost 23 runs true to size and has a slightly wider toe box compared to the Nike Air Max 90. If you wear a US 10 in the Ultraboost 23, your target size for the Air Max 90 is US 9.5.
Nike Air Max 90 → Adidas Ultraboost 23: The Nike Air Max 90 runs about a half-size large and has a slightly narrower toe box compared to the Adidas Ultraboost 23. If you wear a US 10 in the Air Max 90, your target size for the Ultraboost 23 is US 10.5.
Spec comparison
| Spec | Adidas Ultraboost 23 | Nike Air Max 90 |
|---|---|---|
| Length Fit | True to Size | Runs Large (~½ size) |
| Toe Box Profile | Wide | Standard |
| Arch Support | High | Moderate |
| Upper Material | Primeknit Textile | Leather/Mesh |
Size conversion: Adidas Ultraboost 23 → Nike Air Max 90
If you wear these US sizes in the Ultraboost 23, here is the size to order in the Air Max 90.
| Your US size in Ultraboost 23 | Recommended Air Max 90 size |
|---|---|
| US 8 | US 7.5 |
| US 9 | US 8.5 |
| US 10 | US 9.5 |
| US 11 | US 10.5 |
| US 12 | US 11.5 |
Frequently asked questions
Which runs bigger, the Adidas Ultraboost 23 or the Nike Air Max 90?
The Nike Air Max 90 runs longer than the Adidas Ultraboost 23. The Ultraboost 23 is the snugger of the two, so you may want extra length going the other way.
If I wear a US 10 in the Ultraboost 23, what size is the Air Max 90?
Target a US 9.5 in the Air Max 90. A US 9 in the Ultraboost 23 maps to about US 8.5, and a US 11 to about US 10.5.
Is the Ultraboost 23 wider than the Air Max 90?
The Adidas Ultraboost 23 has a slightly wider toe box versus the Nike Air Max 90 (wide vs standard). Forefoot room is one of the biggest reasons two shoes at the same length still feel different.
How do the Ultraboost 23 and Air Max 90 compare on support and material?
The Ultraboost 23 pairs high arch support with a primeknit textile upper; the Air Max 90 has moderate support and a leather/mesh upper.
Try it: adjust the size and compare live
Verdict
The Adidas Ultraboost 23 runs true to size and has a slightly wider toe box compared to the Nike Air Max 90. If you wear a US 10 in the Ultraboost 23, your target size for the Air Max 90 is US 9.5.
| Spec | Adidas Ultraboost 23 | Nike Air Max 90 |
|---|---|---|
| Length Fit | True to Size | Runs Large (~½ size) |
| Toe Box Profile | Wide | Standard |
| Arch Support | High | Moderate |
| Upper Material | Primeknit Textile | Leather/Mesh |