Nike Air Max 90 vs Nike React Infinity Run 4 Sizing
Nike Air Max 90 vs Nike React Infinity Run 4: 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 up from the Nike Air Max 90 to the Nike React Infinity Run 4?
Yes — size up a half size. If you wear a US 10 in the Air Max 90, order about a US 10.5 in the React Infinity Run 4.
How they compare
Nike Air Max 90 → Nike React Infinity Run 4: The Nike Air Max 90 runs about a half-size large and has a slightly narrower toe box compared to the Nike React Infinity Run 4. If you wear a US 10 in the Air Max 90, your target size for the React Infinity Run 4 is US 10.5.
Nike React Infinity Run 4 → Nike Air Max 90: The Nike React Infinity Run 4 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 React Infinity Run 4, your target size for the Air Max 90 is US 9.5.
Spec comparison
| Spec | Nike Air Max 90 | Nike React Infinity Run 4 |
|---|---|---|
| Length Fit | Runs Large (~½ size) | True to Size |
| Toe Box Profile | Standard | Wide |
| Arch Support | Moderate | High |
| Upper Material | Leather/Mesh | Flyknit |
Size conversion: Nike Air Max 90 → Nike React Infinity Run 4
If you wear these US sizes in the Air Max 90, here is the size to order in the React Infinity Run 4.
| Your US size in Air Max 90 | Recommended React Infinity Run 4 size |
|---|---|
| US 8 | US 8.5 |
| US 9 | US 9.5 |
| US 10 | US 10.5 |
| US 11 | US 11.5 |
| US 12 | US 12.5 |
Frequently asked questions
Which runs bigger, the Nike Air Max 90 or the Nike React Infinity Run 4?
The Nike Air Max 90 runs longer than the Nike React Infinity Run 4 — it is large, so size accordingly when moving between them.
If I wear a US 10 in the Air Max 90, what size is the React Infinity Run 4?
Target a US 10.5 in the React Infinity Run 4. A US 9 in the Air Max 90 maps to about US 9.5, and a US 11 to about US 11.5.
Is the Air Max 90 wider than the React Infinity Run 4?
The Nike Air Max 90 has a slightly narrower toe box versus the Nike React Infinity Run 4 (standard vs wide). Forefoot room is one of the biggest reasons two shoes at the same length still feel different.
How do the Air Max 90 and React Infinity Run 4 compare on support and material?
The Air Max 90 pairs moderate arch support with a leather/mesh upper; the React Infinity Run 4 has high support and a flyknit upper.
Try it: adjust the size and compare live
Verdict
The Nike Air Max 90 runs about a half-size large and has a slightly narrower toe box compared to the Nike React Infinity Run 4. If you wear a US 10 in the Air Max 90, your target size for the React Infinity Run 4 is US 10.5.
| Spec | Nike Air Max 90 | Nike React Infinity Run 4 |
|---|---|---|
| Length Fit | Runs Large (~½ size) | True to Size |
| Toe Box Profile | Standard | Wide |
| Arch Support | Moderate | High |
| Upper Material | Leather/Mesh | Flyknit |