Engine Displacement Calculator
Work out engine displacement from bore, stroke and cylinder count in cc, liters and cubic inches, plus static compression ratio from chamber volume.
Interactive calculator · Method ENGINE-DISPLACEMENT-1.0 · Last reviewed: 2026-11-04
Calculate your scenario
Displacement per cylinder = π ÷ 4 × bore² × stroke; total displacement = per-cylinder displacement × number of cylinders.
Your inputs
Default worked example. Edit the inputs to calculate your scenario.
Default worked example
π ÷ 4 × 86 mm² × 86 mm = 499.56 cc per cylinder × 4 = 1,998.2 cc.
How to use the calculator
Choose millimeters or inches, enter the bore and stroke, the number of cylinders and, if you want the compression ratio, the total clearance volume per cylinder in cc.
What the result means
An 86 mm × 86 mm four-cylinder sweeps about 1,998.2 cc (2.0 L, 121.94 in³); with a 55 cc total chamber per cylinder the static compression ratio is about 10.08:1.
Formula and units
Displacement per cylinder = π ÷ 4 × bore² × stroke; total displacement = per-cylinder displacement × number of cylinders. Millimeter results are divided by 1,000 to give cc; inch results are multiplied by 16.387064 cc per cubic inch. Static compression ratio = (swept volume per cylinder + chamber volume) ÷ chamber volume.
Worked examples
86 mm square four-cylinder: Cylinder bore: 86 mm or in; Piston stroke: 86 mm or in; Number of cylinders: 4 cylinders; Combustion chamber volume per cylinder (0 = skip): 55 cc; Bore and stroke unit: mm.
Example result: Total displacement: 1,998.2 cc; Total displacement in liters: 1.998 L; Total displacement in cubic inches: 121.94 in³; Displacement per cylinder: 499.56 cc; Static compression ratio: 10.08:1.
4.00 in × 3.48 in V8: Cylinder bore: 4 mm or in; Piston stroke: 3.48 mm or in; Number of cylinders: 8 cylinders; Combustion chamber volume per cylinder (0 = skip): 76 cc; Bore and stroke unit: in.
Example result: Total displacement: 5,733 cc; Total displacement in liters: 5.733 L; Total displacement in cubic inches: 349.85 in³; Displacement per cylinder: 716.62 cc; Static compression ratio: 10.43:1.
Limitations and common mistakes
Geometric swept volume only. It says nothing about horsepower, torque, emissions or performance. The compression ratio is the static geometric ratio; the chamber volume you enter must already include head chamber, gasket, deck clearance and piston dome or dish volume. Manufacturer displacement figures are often rounded.
Using the head chamber volume alone for the compression ratio. Gasket, deck clearance and piston dish volume all add to the clearance volume and lower the ratio.
Sources and assumptions
Method ENGINE-DISPLACEMENT-1.0; last formula review 2026-11-04. Sources and their supported claims. Calculation methodology.