To provide a pedometer capable of switching a walking mode and a running mode automatically.

A sensor 11 detects vibrations made by walking or running. A control part 4 inputs the vibrations by walking or running detected by the sensor 11, measures a count interval of the vibrations by walking or running, compares the count interval with a threshold, and determines the walking mode or the running mode. A display part 3 displays a screen according to the walking mode or the running mode. In the walking mode, the display part 3 displays items such as number of steps, walking time, walking distance, and calorie consumption. In the running mode, the display part 3 displays items such as running time, running distance, a lap time, and predicted time.