True-to-Size Millimeter Sizing Comparison
Ryka Devotion X Max RS Walking vs Ryka Echo Knit Slip On
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 Devotion X Max RS Walking to see your calculated size in the Echo Knit Slip On.
Complete Size Conversion Matrix
Direct millimeter-calibrated mapping comparing all available sizes between both shoes.
| Devotion X Max RS Walking (US) | Internal Cavity | Echo Knit Slip On Equivalent | Match Accuracy | Fit Difference |
|---|---|---|---|---|
| US 3.5 | 240 mm | US 5.5 | 99% | +0.1 mm |
| US 4 | 243 mm | US 6 | 99% | +0.1 mm |
| US 4.5 | 247 mm | US 6.5 | 99% | +0.1 mm |
| US 5 | 250 mm | US 7 | 99% | +0.1 mm |
| US 5.5 | 253 mm | US 7.5 | 99% | +0.1 mm |
| US 6 | 257 mm | US 8 | 99% | +0.1 mm |
| US 6.5 | 260 mm | US 8.5 | 99% | +0.1 mm |
| US 7 | 267 mm | US 9 | 99% | +0.1 mm |
| US 7.5 | 270 mm | US 9.5 | 99% | +0.1 mm |
| US 8 | 273 mm | US 10 | 99% | +0.1 mm |
| US 8.5 | 277 mm | US 10.5 | 99% | +0.1 mm |
| US 9 | 280 mm | US 11 | 99% | +0.1 mm |
| US 9.5 | 283 mm | US 11 | 65% | -2.9 mm |
| US 10 | 287 mm | US 11 | 18% | -6.9 mm |
| US 10.5 | 290 mm | US 11 | 0% | -9.9 mm |
| US 11 | 293 mm | US 11 | 0% | -12.9 mm |
| US 11.5 | 297 mm | US 11 | 0% | -16.9 mm |
| US 12 | 300 mm | US 11 | 0% | -19.9 mm |
| US 12.5 | 303 mm | US 11 | 0% | -22.9 mm |
| US 13 | 307 mm | US 11 | 0% | -26.9 mm |
| US 14 | 313 mm | US 11 | 0% | -32.9 mm |
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Frequently Asked Questions
How does the Devotion X Max RS Walking size compare to the Echo Knit Slip On?
Both shoes share a very similar length profile. We recommend ordering your standard size in both. The Devotion X Max RS Walking has an internal fit offset of 0.12mm compared to 0.2mm for the Echo Knit Slip On.
Do these shoes fit wide feet comfortably?
The Devotion X Max RS Walking has a snug/narrow width profile, while the Echo Knit Slip On is roomy/wide.