US to UK Shoe Size Conversion
UK men's sizes run one full size below US men's at the same foot length: US 9 equals UK 8. The barleycorn formula is UK = (foot length in inches × 3) − 23. This is why en-GB and en-US charts differ even for the same physical shoe.
Try the conversion
| Foot length (mm) | US Men | US Women | UK | EU | CM |
|---|---|---|---|---|---|
| 237 | 6 | 7.5 | 5 | 36 | 23.5 |
| 246 | 7 | 8.5 | 6 | 37 | 24.5 |
| 254 | 8 | 9.5 | 7 | 38 | 25.5 |
| 262 | 9 | 10.5 | 8 | 39 | 26 |
| 271 | 10 | 11.5 | 9 | 41 | 27 |
| 279 | 11 | 12.5 | 10 | 42 | 28 |
| 288 | 12 | 13.5 | 11 | 43 | 29 |
| 296 | 13 | 14.5 | 12 | 44 | 29.5 |
Quick conversion table
| US Men | UK Men | Foot (mm) |
|---|---|---|
| 6 | 5 | 237 |
| 7 | 6 | 246 |
| 8 | 7 | 254 |
| 9 | 8 | 262 |
| 10 | 9 | 271 |
| 11 | 10 | 279 |
| 12 | 11 | 288 |
| 13 | 12 | 296 |
Formula (Layer A): UK = round_to_half((foot_length_inches × 3) − 23). See how we calculate for the full methodology.
How to read this conversion
The anchor row converts US Men 9 to 262mm first, then displays it as UK Men 8. That millimetre anchor is why the same size can be compared against brand and model fit without re-entering the number.
- Foot length in millimetres is the pivot; brand fit is applied later on brand and model pages.
- US men's labels use the barleycorn formula, then round to the nearest half size.
- UK men's labels run one full number below US men's for the same foot length.
Save this conversion as your size passport
Save your foot length once, then compare brand and model sizing without retyping it.
Local-only by default. Share links include foot length, width and note in the URL, so use them only with people you trust.
What is US size 9 in UK?
US men's 9 equals UK 8 for the same foot length — UK barleycorn sizing runs one full size below US men's.
Brand-specific sizing (Layer B)
Generic charts ignore fit — Nike runs small, New Balance runs large, Converse runs very small. For a purchase-ready answer with confidence score and sources:
Compare brand fit before buying
Length conversion gets you the starting size. Brand fit can still move the label by a half size.
Reverse conversion
Need the other direction? Use UK to US Shoe Size Conversion.