Abstract: A photograph multiplying factor automatic-counting scale including a scale head linearly movable, a pulse generator generating pulse signal per unit length in proportion to movement of said scale head, a BCD counter through which said pulse signal from said pulse generator is converted into BCD code and counted, an interface circuit into which output value from said BCD counter is fed through a BCD decimal converter, and an arithmetic circuit into which output value from said interface circuit is fed through output of a program starting button, so that a length measuring apparatus including said scale head may obtain original dimensions as divisor, whereby said arithmetic circuit divides finished dimensions by said original dimensions and the quotient obtained by said arithmetic circuit is displayed or printed out.