An instantly aligning collet indexer that can be instantly mounted on the standard tooling vises found on most milling machines. A constant clamping pneumatic collet closing system with the valve and manifold is built into the body. The design is compact enough to fit in any standard 6″ machine tool vise and rigid enough to be useful for machining operations. The collet indexer can be used in a vertical or horizontal position in a typical mill vise of a milling machine. The device can be driven by a simple graduated hand crank or by a servo type motor controlled by various programs used in conjunction with a computer.