Jean size calculator
Enter your measurements in centimetres to get your American jean size (W/L).
US jean sizes use the W/L (Waist/Length) system: W = waist in inches, L = inseam in inches. A W32/L32 jean has 32 inches waist and 32 inches inseam. This double measurement lets you fit the cut precisely to your body.
To convert from cm, divide by 2.54 and round: a waist of 81 cm equals W32 (81/2.54 = 31.9 = 32). Manufacturers usually use even increments (W30, W32, W34). If between two, size up for comfort.
- Waist: measure horizontally at the narrowest point, where the belt sits.
- Inseam: measure along the inside of the leg, from groin to floor (or ankle for cropped jeans).
- Note both measurements in centimetres.
- Look up your W and L in inches in the table.
Waist / inseam (cm) to W/L
| Waist (cm) | W (US) | Inseam (cm) | L (US) |
|---|---|---|---|
| 71 | W28 | 76 | L30 |
| 76 | W30 | 81 | L32 |
| 81 | W32 | 86 | L34 |
| 86 | W34 | 91 | L36 |
| 91 | W36 | 96 | L38 |
| 96 | W38 | 101 | L40 |
| 101 | W40 | 106 | L42 |
| 106 | W42 | 111 | L44 |
Frequently asked questions
Why don't my usual jeans match the conversion?
Brands use 'vanity sizing': they label jeans smaller than they actually are. A Levi's W32 might be 84 cm waist, a Diesel W32 might be 81 cm. Compare the actual measurement.
What length (L) for my height?
For 170-175 cm: L30-L32. For 175-180: L32-L34. For 180-185: L34. Above 185: L36. Varies by brand and cut (vintage often has longer legs).
Do jeans shrink in the wash?
Raw denim shrinks up to 5% on first wash. Pre-washed (sanforized) jeans shrink little (1-2%). When buying raw, size up in waist and length.
How do I know the W of an existing jean?
Measure the waist of the jean laid flat (top, just under the belt), multiply by 2, divide by 2.54. Example: 41 cm × 2 = 82 cm / 2.54 = 32. So W32.