Engine specifications can be confusing, especially when different manufacturers list power in different units.

Some use cubic centimeters (CC), others use horsepower (HP), and performance enthusiasts often want to understand how those numbers relate.

This calculator helps you convert between CC and HP instantly while also giving extra context like liters, cubic inches, kilowatts, watts, and HP per liter.

What this calculator does

Whether you are comparing motorcycles, outboard motors, power equipment, or small engines, this tool gives you:

• Accurate CC ↔ HP conversions
• Final CC and final HP values
• Liters and cubic inches for better displacement comparisons
• Kilowatts and watts for international power ratings
• HP per liter, a helpful measure of engine efficiency and tuning potential

It is built for both beginners and gearheads who want a quick reference without digging into technical charts.

Why CC and HP don’t always match perfectly

Unlike simple unit conversions, CC and HP are not directly interchangeable.

CC measures engine displacement, the total volume of the cylinders, while horsepower measures engine output.

Two engines with the same displacement can produce very different horsepower depending on:

• Compression ratio
• Fuel delivery and tuning
• Number of cylinders
• Turbocharging or supercharging
• Efficiency of the intake and exhaust systems

Because of that, most CC to HP estimates rely on common real world averages. This calculator uses widely accepted industry ratios while giving you the complementary numbers that help you compare engines more fairly.

When this tool is especially useful

People use CC ↔ HP conversions for all sorts of decisions:

• Comparing motorcycles with different engine sizes
• Estimating the power of older engines with missing documentation
• Understanding how a lawnmower or generator stacks up against modern models
• Looking at outboard motor ratings for boats
• Planning upgrades or engine swaps
• Translating specs when shopping internationally

Many riders and boat owners just want a simple way to understand whether an engine is underpowered, overpowered, or well balanced. That is exactly what this tool is designed to do.

How the conversion works

While the raw math depends on the engine type, a common approximation used across small to mid displacement engines is:

• 1 HP ≈ 15–17 CC
• CC ÷ 15 ≈ HP

This calculator handles the computation automatically and rounds the results into practical numbers.

It also provides:

• Liters: CC ÷ 1,000
• Cubic inches: CC ÷ 16.387
• Kilowatts: HP × 0.7457
• Watts: kW × 1,000
• HP per liter: HP ÷ Liters

These extra data points help you compare engines across regions, especially since European, Asian, and U.S. manufacturers often use different rating standards.

Tips for interpreting your results

It is always good to remember that displacement is only part of the story.

• Higher HP per liter usually means a more refined or performance oriented engine.
• Large CC with low HP often indicates an engine designed for longevity or torque rather than peak power.
• Boats and off road equipment typically favor torque, not just HP, so CC can matter more there.
• Motorcycles and performance engines tend to break the rules — a 600cc sportbike easily makes more HP than many 1,000cc cruisers.

Try it out

Choose whether you want to solve for CC or HP, enter your known value, and let the calculator handle everything else.

You will get a full breakdown of displacement, power, and conversion metrics in seconds.