The WindSonic, manufactured by Gill Instruments Ltd., is a two-dimensional ultrasonic anemometer for measuring wind speed and direction.

The WindSonic is an alternative to traditional mechanical cup and vane or propeller and vane anemometers. Unlike mechanical anemometers, there are no moving parts to be replaced periodically, minimizing routine maintenance. The minimum detectable wind speed is 0.01 meters per second.

The WindSonic easily interfaces to a Campbell Scientific datalogger through a control port, 12 Vdc, and ground. Current drain is 40 mA continuous. The SDI-12 instruction is used to collect data from the WindSonic; up to 10 WindSonics can be connected to one datalogger control port.