Engine Capacity Calculator — Displacement in CC, Liters and CID

What Is Engine Displacement?

The total volume all pistons sweep — the “size” of the engine. A 2.0L moves 2 liters of air-fuel mix per cycle. Bigger generally means more power potential, but turbocharging and efficiency matter more today.

Bore vs Stroke

• Oversquare (bore over stroke): revs high, loves RPM — sports cars, motorcycles.
• Square (equal): balanced — the 86x86mm “square” engine is a classic.
• Undersquare (stroke over bore): torquey down low — trucks, diesels.

Quick Conversions

• 1 liter = 1,000 cc = 61.02 cubic inches.
• A “350” small block = 350 CID is about 5.7L. A “302” = 5.0L.

Engine Capacity vs Displacement: What is the Difference?

None – they mean the same thing. Both refer to the total swept volume of all the pistons in an engine. “Displacement” is the common term in the US, while “capacity” is the common term in the UK, India, Australia and most other markets outside the US.

So a 2.0L engine has 2.0L of displacement and 2.0L of capacity – 2,000 cc, or about 122 cubic inches. If you see “engine capacity” on a spec sheet, read it exactly as you would read “engine displacement.”

How to Calculate Engine Capacity (Formula + Example)

Use this formula:

Capacity = pi / 4 x bore squared x stroke x cylinders

If bore and stroke are in mm, the result is in cubic mm – divide by 1,000 to get cc, then divide by 1,000 again to get liters.

Example 1 – 86 mm bore x 86 mm stroke x 4 cylinders: pi / 4 x 86 squared x 86 x 4 / 1,000 = about 1,998 cc (2.0L). This is the same figure the calculator above shows for these inputs.

Example 2 – Chevy 350 (4.00 in bore x 3.48 in stroke x 8 cylinders): pi / 4 x 4.00 squared x 3.48 x 8 = about 350 cubic inches (5.7L). That is where the “350” name comes from.

Engine Capacity in CC for Motorcycles and Bikes

Motorcycle and bike engines are almost always quoted in cc, and most are single-cylinder – so the capacity is just one cylinder’s volume. Enter your bike’s bore and stroke above and set cylinders to 1.

• 125cc: typical commuter bike – light, fuel-efficient, easy to ride in city traffic. About 7.6 cubic inches.
• 150cc: a step up in power for commuting and short highway rides. About 9.2 cubic inches.
• 250cc: comfortable for highway speeds, with noticeably more torque than a 125cc. About 15.3 cubic inches.

Because a bike engine has just one or two cylinders, a small change in bore or stroke makes a big percentage difference – that is why 125cc and 150cc bikes feel so different despite only 25cc between them.

Common Engine Capacities: CC, Liters and CID

Use this table to convert the sizes you see most often:

Note: the classic Ford 302 is 302 CID, which is 4.9L – very close to, but not exactly, 5.0L.

Engine Capacity vs EV Motors (kW)

Electric cars do not have engine capacity at all – there are no pistons, no cylinders, and nothing to displace. An EV motor is measured in kW for power and kWh for battery size, not in cc or liters.

As a rough guide, a 2.0L petrol engine making about 150 hp is comparable in power to an EV motor rated around 110 kW. The difference is that the EV delivers its torque instantly, with no gears and no fuel to burn.

If you are comparing a petrol car with an electric one, capacity alone will not tell you the running cost. Use our EV vs Gas Cost Calculator to compare fuel and charging costs side by side.