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How many crankshaft revolutions are needed for one four-stroke engine cycle?

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Labeled cross-sectional diagram of a V-type gasoline engine for an automobile, showing internal components such as pistons, crankshaft, camshaft, intake and exhaust valves, connecting rods, spark plugs, and intake manifold. — gasoline engine Cross section of a V-type engine.

A four-stroke cycle engine requires two full revolutions of the crankshaft to complete one full cycle.12

During this process, the piston completes four distinct strokes—intake, compression, power, and exhaust—which correspond to the two rotations of the crankshaft.12