A compressor includes a housing; an impeller rotatably installed in the housing; a guidance unit connected to the housing at a first end of the guidance unit and configured to guide a fluid discharged by the impeller, the guidance unit configured to change a flow direction; and a scrolling unit connected to a second end opposite to the first end of the guidance unit. A width of an opening via which the fluid enters a circular space of the scrolling unit is about 1.5 to about 3.5 times a height of the guidance unit.