What instrument do you use to measure wind speed?

The instrument used to measure wind speed is an anemometer. It is a standard meteorological device found at weather stations, airports, ships, wind farms, and research sites.

The familiar cup anemometer has three or four cups mounted on horizontal arms. Wind pushes the cups around a vertical shaft, and the rotation rate is converted into a wind-speed reading. Because the cups rotate regardless of the wind’s horizontal direction, this design is especially useful for measuring how fast the air is moving. A separate vane is often added to determine wind direction.

The earliest known description of an anemometer dates to 1450, when Italian architect and author Leon Battista Alberti described a device for assessing wind strength. In 1846, Irish astronomer Thomas Romney Robinson improved the design with four hemispherical cups. Modern instruments may instead use ultrasonic pulses, measuring how wind changes the travel time of sound. Wind speed is commonly reported in metres per second, kilometres per hour, or miles per hour.