: Crucial for those with a more athletic build; measure the widest part of your upper leg.

: Measure around your natural waistline, usually just above the belly button. Keep the tape snug but breathable.

Standard sizes (S/M/L) or even waist numbers (32, 34) vary wildly between brands due to "vanity sizing". For a perfect fit, use a cloth tape measure for the following:

: Measure around the fullest part of your posterior to ensure the pants don't pull or sag in the back.