Abstract: A production tool wear detector which provides a direct, non-contact measurement of the amount of material removed from a cutting tool due to wear during operation thereof. One or more sensing devices monitor the distance to a selected wearing cutting surface of the tool and the distance to a selected non-wearing reference surface of the tool and such distances are suitably processed by appropriate electronic circuitry so as to provide a signal representing the wear characteristics of such cutting surface, which signal can be appropriately displayed, or otherwise used, to make an operator aware of when the tool has worn to a point below a selected threshold. Such a system permits in situ, continuous monitoring of one or more cutting tools during actual use of the tools in a consistent and accurate fashion at relatively low cost.