Many web producers sell rolls of a specified length. Shipping short rolls is unacceptable while overlong rolls are costly. How are we to ship rolls with a close tolerance on length? Commonly used sensors are based on “footage” wheels, “dead reckoning”, or laser interferometry. Quality checks or complaints by customers raise many questions about length measurement. Length measurement is a 1 dimensional (1D) location problem with one axis of control. A lot of research has gone into the precise location of vehicles (2D) and robot effectors (3D). We will compare traditional length measurement sensors and look for opportunities for greater accuracy by combining multiple measurement methods with modern mathematics.