True-to-Size Millimeter Sizing Comparison
Allbirds Tree Runner vs ASICS GEL-Kayano 32
Detailed size conversion chart, cavity measurements in millimeters, and crowd-sourced fit advice for choosing your perfect size.
Interactive Size Converter
Select what size you wear in the Tree Runner to see your calculated size in the GEL-Kayano 32.
Complete Size Conversion Matrix
Direct millimeter-calibrated mapping comparing all available sizes between both shoes.
| Tree Runner (US) | Internal Cavity | GEL-Kayano 32 Equivalent | Match Accuracy | Fit Difference |
|---|---|---|---|---|
| US 3.5 | 240 mm | US 4 | 88% | +1.0 mm |
| US 4 | 243 mm | US 4.5 | 64% | +3.0 mm |
| US 4.5 | 247 mm | US 5 | 52% | +4.0 mm |
| US 5 | 250 mm | US 5 | 88% | +1.0 mm |
| US 5.5 | 253 mm | US 5.5 | 64% | +3.0 mm |
| US 6 | 257 mm | US 6 | 52% | +4.0 mm |
| US 6.5 | 260 mm | US 6 | 88% | +1.0 mm |
| US 7 | 267 mm | US 7 | 82% | +1.5 mm |
| US 7.5 | 270 mm | US 7.5 | 88% | +1.0 mm |
| US 8 | 273 mm | US 8 | 64% | +3.0 mm |
| US 8.5 | 277 mm | US 8.5 | 52% | +4.0 mm |
| US 9 | 280 mm | US 8.5 | 88% | +1.0 mm |
| US 9.5 | 283 mm | US 9 | 64% | +3.0 mm |
| US 10 | 287 mm | US 9.5 | 52% | +4.0 mm |
| US 10.5 | 290 mm | US 9.5 | 88% | +1.0 mm |
| US 11 | 293 mm | US 10 | 64% | +3.0 mm |
| US 11.5 | 297 mm | US 10.5 | 82% | +1.5 mm |
| US 12 | 300 mm | US 11 | 88% | +1.0 mm |
| US 12.5 | 303 mm | US 11.5 | 64% | +3.0 mm |
| US 13 | 307 mm | US 12 | 52% | +4.0 mm |
| US 14 | 313 mm | US 12.5 | 64% | +3.0 mm |
Related Comparisons
Direct RivalryDuramo SL 10 vs Tree RunnerView Sizing ComparisonDirect RivalryAdizero EVO SL vs Tree RunnerView Sizing ComparisonDirect RivalryTree Runner vs Bondi Slip ResistantView Sizing Comparisonallbirds ComparisonTree Runner vs Wool RunnerView Sizing ComparisonDirect RivalryDuramo SL 10 vs GEL-Kayano 32View Sizing ComparisonDirect RivalryAdizero EVO SL vs GEL-Kayano 32View Sizing Comparison
Frequently Asked Questions
How does the Tree Runner size compare to the GEL-Kayano 32?
Both shoes share a very similar length profile. We recommend ordering your standard size in both. The Tree Runner has an internal fit offset of -0.2mm compared to -0.16mm for the GEL-Kayano 32.
Do these shoes fit wide feet comfortably?
The Tree Runner has a snug/narrow width profile, while the GEL-Kayano 32 is snug/narrow.