A conical mill (or conical screen mill) is a machine used to reduce the size of material in a uniform manner.

As the name implies, the conical mill varies in diameter from where the feed enters to where the product exits.

The conical mill operates by having the product being fed into the mill by gravity or vacuum. A rotating impeller forces the material outward to a conical screen surface, where it is sized and passed through the openings in the screen. Once finished, the product simply drops through the milling chamber to a receptacle underneath.