Physics
Instant, private, and free
Engine Displacement Calculator.
Calculate swept engine displacement from bore, stroke, and cylinder count.
Set your values
Results update as you type.
Educational SI model using the assumptions stated above; verify engineering and safety decisions independently.
Use Cases
Engine Specification Verification
Check if an engine's displacement matches its advertised specs by entering the bore, stroke, and cylinder count.
Example: Bore 0.086 m, stroke 0.086 m, 4 cylinders → 1998 cc
Custom Engine Building
Estimate the displacement of a modified engine when changing bore or stroke, helping to plan performance upgrades.
Example: Increase bore from 0.086 m to 0.088 m to see displacement change.
Frequently Asked Questions
- How is engine displacement calculated?
- Displacement is the swept volume of all cylinders. It is calculated using the formula: displacement = (π/4) × bore² × stroke × number of cylinders. This calculator uses bore and stroke in meters and cylinders count to compute the total swept volume.
- What units does this calculator use?
- The calculator accepts bore and stroke in meters (m) and cylinders as a count. The result is provided in cubic centimeters (cc) and liters (L), which are common for engine displacement.
- Can I use this for any engine type?
- Yes, as long as you know the bore, stroke, and number of cylinders. It works for car, motorcycle, and small engines. The formula assumes a standard cylindrical combustion chamber shape.
Tips & Common Mistakes
Tips
- Ensure bore and stroke are in meters. Convert from millimeters by dividing by 1000.
- Use the same precision for all measurements to get accurate results.
- Double-check the cylinder count; for V engines, it's the total number of cylinders.
- The result is swept volume, not total engine volume including combustion chambers.
Common Mistakes to Avoid
- Entering bore and stroke in millimeters instead of meters, leading to incorrect results.
- Using the diameter of the bore instead of the radius in the formula (the calculator uses bore directly).
- Confusing swept volume with total engine capacity that includes clearance volume.
Last updated: August 13, 2026