To provide a frequency division ratio output device for a frequency divider with simple configuration, which sets a frequency division ratio to a value that is not higher than a decimal point and outputs the frequency division ratio.

This frequency division ratio output device is provided with a reference value setter 12 for setting a reference value for calculating a frequency division ratio to a value 65.5 down to n decimal places, an integer/decimal divider 14a for dividing the set reference value into the integer part 65 and the decimal 0.6 with n places and outputting the resultant numbers, a decimal adder 14b for receiving and adding outputted decimals, and outputting added decimals as an integer 1 when the added decimals is a value that is equal to or greater than the integer 1, and a frequency division ratio adder 14c for receiving the value of an outputted integer part, adding an integer 1 to the received value of the integer part when the integer 1 is outputted and meanwhile outputting the received value of the integer part as it is when the integer 1 is not outputted. The device regards the outputted value as a frequency division ratio, and frequency dividing an input signal (output pulse of rotation sensor 22) with the frequency division ratio to generate an output signal.