True-to-Size Millimeter Sizing Comparison
Brooks Addiction GTS 15 vs Brooks Adrenaline GTS 25
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 Addiction GTS 15 to see your calculated size in the Adrenaline GTS 25.
Complete Size Conversion Matrix
Direct millimeter-calibrated mapping comparing all available sizes between both shoes.
| Addiction GTS 15 (US) | Internal Cavity | Adrenaline GTS 25 Equivalent | Match Accuracy | Fit Difference |
|---|---|---|---|---|
| US 4.5 | 229 mm | US 4.5 | 53% | +4.0 mm |
| US 5 | 233 mm | US 4.5 | 100% | 0.0 mm |
| US 5.5 | 236 mm | US 5 | 88% | +1.0 mm |
| US 6 | 239 mm | US 5.5 | 88% | +1.0 mm |
| US 6.5 | 243 mm | US 6 | 100% | 0.0 mm |
| US 7 | 246 mm | US 6.5 | 88% | +1.0 mm |
| US 7.5 | 249 mm | US 7 | 88% | +1.0 mm |
| US 8 | 253 mm | US 7.5 | 100% | 0.0 mm |
| US 8.5 | 256 mm | US 8 | 88% | +1.0 mm |
| US 9 | 263 mm | US 8.5 | 65% | -3.0 mm |
| US 9.5 | 266 mm | US 9 | 88% | +1.0 mm |
| US 10 | 269 mm | US 9.5 | 88% | +1.0 mm |
| US 10.5 | 273 mm | US 10 | 100% | 0.0 mm |
| US 11 | 276 mm | US 10.5 | 88% | +1.0 mm |
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Frequently Asked Questions
How does the Addiction GTS 15 size compare to the Adrenaline GTS 25?
The Adrenaline GTS 25 provides about 4mm more internal length than the Addiction GTS 15. We suggest ordering 1/2 size down in Adrenaline GTS 25. The Addiction GTS 15 has an internal fit offset of -4mm compared to 0mm for the Adrenaline GTS 25.
Do these shoes fit wide feet comfortably?
The Addiction GTS 15 has a standard medium width profile, while the Adrenaline GTS 25 is standard medium.