A utility knife including: a body defining an interior cavity, and a blade carriage slidably disposed within the cavity. The blade carriage is configured for removably receiving at least one blade, and is at least partially slidably removable from the cavity, thereby allowing facile replacement of the blade. In one embodiment, the carriage may receive first and second blades, each of which is extensible from an associated end of the body. A utility knife blade including dual cutting edges and cutting points is also provided.