Sizing a paddle depends on various factors, and if you are a seasoned paddler, you probably know what length/width you want. Mostly, I wouldn't expect to have anyone who has a lot of paddling experience ask me about length or width. And frankly, really nailing the proper length does require some seasoning. However, to simplify, a person of average torso/overall body length measurements, should just measure from about mid chest to the ground, while standing. That gives you a good approximation of where you ought to be. If you are paddling on a team, and paddlers about your height seem to be using longer or shorter paddles, then you should factor that into your measurement. Longer paddles mean extra leverage; shorter paddles less leverage -- and most likely, a higher cadence.