True-to-Size Millimeter Sizing Comparison
Naturalizer Flexy Ballet Flat vs Naturalizer Marianne
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 Flexy Ballet Flat to see your calculated size in the Marianne.
Complete Size Conversion Matrix
Direct millimeter-calibrated mapping comparing all available sizes between both shoes.
| Flexy Ballet Flat (US) | Internal Cavity | Marianne Equivalent | Match Accuracy | Fit Difference |
|---|---|---|---|---|
| US 4.5 | 233 mm | US 4.5 | 99% | +0.1 mm |
| US 5 | 237 mm | US 5 | 99% | +0.1 mm |
| US 5.5 | 240 mm | US 5.5 | 99% | +0.1 mm |
| US 6 | 243 mm | US 6 | 99% | +0.1 mm |
| US 6.5 | 247 mm | US 6.5 | 99% | +0.1 mm |
| US 7 | 250 mm | US 7 | 99% | +0.1 mm |
| US 7.5 | 253 mm | US 7.5 | 99% | +0.1 mm |
| US 8 | 257 mm | US 8 | 99% | +0.1 mm |
| US 8.5 | 260 mm | US 8.5 | 99% | +0.1 mm |
| US 9 | 267 mm | US 9 | 99% | +0.1 mm |
| US 9.5 | 270 mm | US 9.5 | 99% | +0.1 mm |
| US 10 | 273 mm | US 10 | 99% | +0.1 mm |
| US 10.5 | 277 mm | US 10.5 | 99% | +0.1 mm |
| US 11 | 280 mm | US 11 | 99% | +0.1 mm |
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Frequently Asked Questions
How does the Flexy Ballet Flat size compare to the Marianne?
Both shoes share a very similar length profile. We recommend ordering your standard size in both. The Flexy Ballet Flat has an internal fit offset of 0.16mm compared to 0.28mm for the Marianne.
Do these shoes fit wide feet comfortably?
The Flexy Ballet Flat has a roomy/wide width profile, while the Marianne is snug/narrow.