Power To Weight Ratio Calculator

Whether you're a car enthusiast, a manufacturer, or an engineer and you're curious about how to compare and evaluate the performance of different vehicles, that's where our power-to-weight ratio calculator comes in.

What is the power to weight Ratio?

The power to weight ratio concept is quite simple; it's a measure of how much power a vehicle has relative to its weight. It tells you how well a vehicle accelerates and performs.

A high power to weight ratio of vehicle means better performance, no matter if it's high performance supercar, a truck or even a motorcycle. It gives you a clear idea of how quickly a vehicle can accelerate and how efficient it is.

How to Calculate the Power-to-Weight Ratio?

There’s nothing easier! Enter the power and weight of your vehicle and see the results. You can switch units easily because every input includes a unit switcher. If you're unsure how the power to weight ratio is calculated or what equation is used to determine it, keep reading. In the next section we explain everything.

Power-to-Weight Ratio Formula

You have to follow these steps in order to calculate the power to weight ratio of your vehicle manually:

• Find the power: First you have to find the peak power output of your vehicle (in hp or KW). You can typically find that via online search or from the owner's manual.
• Find the Curb Weight: You have to find out the curb weight of your vehicle with a full tank of fluids or gas, but keep in mind without cargo or passengers.

Now, plug the values into the formula; here is the simple formula:

Power to Weight Ratio = Power / Weight

Keep in mind to use the consistent units for the weight and power (e.g. hp/lb or kW/kg).

Formula for hp per pound (hp/lb)

HP per pound (hp/lb) is considered one of the most common units in the USA. Here's the equation

P/W ratio = horsepower (hp) / weight in pounds (lb)

For instance:

If your vehicle has 250 hp and weighs 3,000 lb.

P/W ratio = 250 / 3000 = 0.083 hp per lb

Formula for Kilowatt per Kilogram (kW/kg)

Here is the formula for kilowatt per kilogram:

P/W ratio = kW / weight in kg

Example:

P/W ratio = 200 kW / 1250 kg = 0.16 kW per kg

Formula for hp per ton (hp/ton)

The horsepower per ton is very common in the Europe and used for car performance comparisons. Here's the formula:

P/W ratio = horsepower / weight in metric tons

Example:

If your car's power is 350 hp and weight is 1.6 tons:

• 1 metric ton = 1000 kg
• P/W ratio =  350 hp / 1.6 tons = 218.75 hp per ton

Formula for Watt per kilogram (W/kg)

Watt per kilogram equation is commonly used in engineering, small engines and cycling. Here's the formula:

P/W ratio = watts / weight in kg

Example:

P/W ratio = 400 watts / 80 kg = 5 W per kg

However, the formulas are quite simple and straightforward but with different units of power and weight it gets complicated, that's where our tool helps!

Car Power-to-Weight Ratios

Power to weight ratio is the method used to compare how quickly a car can accelerate based on how much power it has for its weight. Here are the typical ranges:

• Sedans: 0.06–0.10 hp/lb
• SUVs: 0.05–0.08 hp/lb
• Sports cars: 0.10–0.20 hp/lb
• Supercars: 0.20–0.30 hp/lb

For example, the Mustang GT has a power to weight ratio of 0.12 hp/lb, Toyota Supra has 0.11 hp/lb, and Tesla Model 3 Performance is 0.14 hp/lb.

Motorcycle Power-to-Weight Ratios

A motorcycle is much lighter compared to a car, so its power to weight ratio is much higher. Here are the typical ranges of bikes:

• 300cc bikes: 0.09–0.125 hp/lb
• 600cc bikes: 0.24–0.31 hp/lb
• 1000cc superbikes: 0.37–0.48 hp/lb

Real World example of calculating the power to weight ratio

For example, let’s compare these two vehicles:

• Chevrolet Silverado 1500 (Full-Size Pickup Truck):
   Power = 355 hp (265 kW), Weight = 4,500 lb (2,041 kg)
• Chevrolet Malibu (Mid-Size Sedan):
   Power = 160 hp (119 kW), Weight = 3,500 lb (1,588 kg)

Let's compare both vehicles as they are from the same manufacturer but their power and weight are different.

Power-to-Weight Ratio Calculations:

• Silverado 1500 Pickup Truck:

  PWR of Silverado = 355 hp / 4500 lb = 0.079 hp/lb

• Chevrolet Malibu Sedan:

  PWR of Malibu = 160 hp / 3500 lb = 0.046 hp/lb

What does that tell Us?

As we did compare performance of different 2 vehicle, as we can see that the Chevrolet Silverado 1500 Pickup Truck has a higher power-to-weight ratio than the Chevrolet Malibu Sedan so this means the Chevrolet Silverado pickup truck is more powerful and accelerate faster and performs better compared to the Chevrolet Malibu Sedan.

What is considered a good power to weight ratio?

Power to weight ratio depends on the vehicle category. Car P/W ratios are compared within car groups, and motorcycle P/W ratios are compared within motorcycle groups because of the big difference in weight.

What Is a Good Power-to-Weight Ratio for Cars?

P/W ratios for cars can range from slow 0.06 hp/lb to fastest 0.20+ hp/lb. Here is the performance breakdown:

Good P/W Ratios for Motorcycles?

It ranges from a basic bike 0.09 hp/lb to fastest superbikes around 0.48 hp/lb. Here are the ranges: