Engine Displacement Calculator

Displacement is the total volume the pistons sweep as they travel from the bottom to the top of their stroke, added across every cylinder. It is a rough guide to how much air and fuel an engine can move per cycle, and therefore to its potential power.

Per cylinder volume is pi divided by 4, times the bore squared, times the stroke, which is the volume of a cylinder. Multiply that by the number of cylinders for the total. This tool works in millimetres, so it divides by 1000 to report the answer in cubic centimetres.

Litres are cc divided by 1000, so 1,998 cc is about 2 litres. Cubic inches are cc divided by 16.387064, so 1,998 cc is roughly 121.94 cubic inches. The calculator shows all three at once.

Marketing rounds displacement to a tidy figure, so a 1,998 cc engine is sold as a 2.0. Real bore and stroke often carry extra decimals, and tolerances vary, so the exact math lands just above or below the round number on the badge.

No. Displacement is only the swept volume between the piston's bottom and top positions. The extra space above the piston at top dead centre is the clearance volume, and it factors into the compression ratio rather than displacement.

Not always. Forced induction, higher rpm and better airflow can let a small engine outpower a larger one. Among similar naturally aspirated engines, though, more displacement usually means more torque and power.

Bore is the cylinder's diameter and stroke is how far the piston travels inside it. An engine with equal bore and stroke is called square; a wider bore than stroke is oversquare and tends to rev higher, while a longer stroke is undersquare and favors low-end torque.

Yes. The calculation runs entirely in your browser, so the bore, stroke and cylinder count you type are never sent to a server.