Northern Pike Weight Formula
The formula to calculate the weight for a Northern Pike that is 40 inches long and has a girth of 22 inches is as follows. Pike have a shape factor of 1300.
WEIGHT = LENGTH x GIRTH2 / SHAPE FACTOR
WEIGHT= 40 x (222) / 1400
WEIGHT= 40 x 484 / 1400
WEIGHT= 19360 / 1400
WEIGHT = 13.82 pounds (This would be a skinny Pike)