A fan assembly including a base arranged to support the fan assembly on a surface, an air flow generator that is arranged to generate an air flow, and an air outlet that is arranged to emit at least a portion of the air flow from the fan assembly is provided. The air outlet is arranged to be oscillated relative to the base. The fan assembly further includes a controller that is arranged to control the oscillation of the air outlet relative to the base. The controller is arranged to vary an oscillation speed of the air outlet for each oscillation.