Letter to FR jeans size
The short answer
By the formula, Letter M is FR 40 to 42.
No brand chart we have checked prints both systems, so this table is the arithmetic alone. Treat it as the label convention, not a fit.
| Letter | FR |
|---|---|
| XXS | 30 |
| XS | 32 to 34 |
| S | 36 to 38 |
| M | 40 to 42 |
| L | 44 to 46 |
| XL | 48 to 50 |
| XXL | 52 to 54 |