This paper presents a feasible machining test to measure, compare and predict the machinability of different titanium alloys. A drilling test was developed and investigated on the two most common grades of titanium, commercial purity and Ti6Al4V. The experiments and analysis revealed that tool wear followed a characteristic pattern for all machining conditions investigated. When machining Ti6Al4V, tool life was shorter and cutting forces higher compared with commercial purity Ti. Paradoxically, despite the more difficult machining, Ti6Al4V samples had better surface integrity than commercial purity samples. A procedure was developed that could be incorporated into a real-time process monitoring device to warn of imminent tool failure.