This may sound like a simple task to you but not everyone knows how to measure jeans and pants to accurately describe them. There are 3 basic things people want to know. Rise - Inseam - and waist.

1. The "rise" of a jeans is determined by the distance between the crotch and the waist and is usually around 12 inches on regular pants. In comparison, the average measurement of low-rise jeans is roughly 8 inches, with some as little as 3-4 inches. They are intended to sit about 3 inches below the belly button.Low rise jeans are also called lowcut jeans, hipsters, hip-huggers and lowriders) jeans are very popular today.

2. To measure "inseam", stand up straight with his legs slightly apart. Using measuring tape, measure from just below the crotch to the bottom of the ankle. Record the length in inches; this is the "inseam".

3. The easiest way to measure the "waist" on a pair of jeans is hold the pants up flat and stretch the tape measure from one side of the inside waistband to the other side. Don't stretch the pants if they have stretch in them. Then you just double the number- example 12" across = 24" waist.
   

This is pretty basic, but like I said many have no idea. I read one auction for jeans with a 47 inch inseam. the person was measuring from the top button to the bottom hem.

Hope this was helpful. Please vote YES for me :)