Abstract: A key blank impressioning tool has a pair of pivotally, interconnected parts for manipulation by the hands of the user. As one of the parts is grasped by one hand to apply torque to the key blank in the keyway of the lock to in turn tend to turn the plug of the lock, the second part of the tool is used by the other hand of the operator for the purpose of reciprocating a block so as to strike light blows of such nature as to create indentations in one edge of the blank to thereby identify the location and depth of the tumbler cuts to be made in the key blank.