A magnetic detector comprises a first magnetic sensor configured to measure a first magnetic field component, a second magnetic sensor configured to measure a possible magnetic field component, a processor, and a memory configured to store a program. The program comprises closest proximity detection processing of detecting a timing at which the magnetic body passes a closest proximity position, closest proximity position component acquisition processing of acquiring the first magnetic field component measured at the timing and the possible magnetic field component, predetermined position component acquisition processing of acquiring the first magnetic field component when the magnetic body is at a predetermined position, distance estimation processing of estimating a third direction distance, and magnetic moment amount estimation processing of estimating a magnitude of the magnetic moment.