HOW TO SIZE A PADDLE
The best way to size a paddle is on the water in your own canoe. Hold your arm out horizontally at shoulder height and measure from your hand to the water. The distance should equal the shaft length from the top of the grip to the throat of the blade.
This measurement can be approximated by sitting upright on a flat chair and placing the paddle upside-down, with the grip on the seat between your legs. The throat should be at eye level. Length adjustments should be made for seat height and paddling style.
Shaft length plus blade height equals paddle size.