The cutting tool for machining valve seats comprises a driving system, a spindle assembly, and a system controller. The driving system provides rotational movement and vertical movement for the spindle assembly which is controlled by the system controller. The spindle assembly further comprises a spherical sheath providing capability to align a spindle to any valve seat orientation, the spindle for rotating a universal cutting blade, a machining head attachable to the spindle, a tool holder carriage for holding the universal cutting blade, and a pinion feed driving assembly or set of connecting rods for controlling the cutting radius of the universal cutting blade. The pinion feed driving assembly is driven by a servo motor which moves the spindle vertically and independent from the vertical movement of the spindle assembly and the rotational movement of the spindle. The system controller includes memory and programming for controlling the operation of the universal cutting blade. An operator can input the parameters that define the geometry of the valve seat profile. These parameters are used by the system controller to determine the rotational speed, the vertical feed of the machine spindle, and the inward or outward feed of the universal cutting tool.