To determine your desired Outseam length, measure a pair of boardshorts from the top of the waistband to the bottom of the leg-opening as shown. If you don’t have access to or own a pair of boardshorts the standard Outseam length is 20 inches and typically lands just above the knee cap. Add additional inches if desired

To determine your desired Waist size, wrap a tape measure around the point on your hips were you want the shorts to hang. If you don’t have access to or own a tape measure a reasonably good measure is to go one size up on your favorite pair of jeans. So if your jeans are a Waist of 32 inches, you’re probably best served with a 34 inch Waist boardshort.