A cutting tool is a device used to remove material from a workpiece by means of shear deformation). It is a wedge-shaped and sharp-edged device that is rigidly mounted on a machine tool and used to obtain the desired shape, size, and accuracy of the workpiece. The purpose of a cutting tool is to compress a particular layer of work material to shear it off, requiring minimum power. Cutting tools are used in a wide range of manufacturing and machining processes.

There are different types of cutting tools, including linear cutting tools such as tool bits and broaches, and rotary cutting tools such as drill bits, countersinks, and counterbores, taps and dies, reamers, and cold saw blades). Other cutting tools, such as bandsaw blades, hacksaw blades, and fly cutters, combine aspects of linear and rotary motion). Cutting tools can also be designed with inserts or replaceable tips made of materials such as cemented carbide, polycrystalline diamond, and cubic boron nitride).

The geometry of a cutting tool encompasses the inclination and orientation of various planes and cutting edges of the tool, as well as the nose radius. The designation of a cutting tool is based on its geometry and the application for which it is used.

Examples of commonly used cutting tools include single-point turning tools, drills, milling cutters, chop saws, and pipe cutters. Cutting tools can also be made of different materials, such as ceramics, high-speed tool steel, cemented carbide, and diamond/CBN.

It is important to optimize the cutting conditions, including the cutting speed, feed rate, and depth of cut, to ensure a long working life for the cutting tool). Safety is also a crucial consideration when using cutting tools, and non-sparking and non-magnetic safety tools are available for certain applications.