Abstract: A device and method for measuring, calculating and displaying swim related information includes a waterproof enclosure with an internal microcomputer programmed to calculate various indicators of swim performance including number of strokes, stroke cycle, stroke rate, velocity and swim stroke efficiency among others. The device is self contained and strapped to the swimmer's wrist during swimming. Function buttons on the exterior of the device control its operation and allow the swimmer to select from various exercise modes and display features. A swim stroke is detected by the use of metallic sensors which extend along the top surface of the device. The sensors act as a short circuit when submerged in water to cause an interrupt condition of the internal microprocessor corresponding to a stroke. The device is secured to a swimmer's wrist by one or more adjustable straps.