An original procedure for the determination of the optimum value of tool life criterion of cutting tools tooled with throw-away carbide tips is described in this paper. The procedure has the character of an iterative method, on the basis of which one can reach the optimum value of tool life criterion with respect to attaining the minimum machining cost. The algorithm of the given method is represented in a bar chart, where we can see two calculation cycles, their purpose and other relationships. A practical example closes the paper.