How to Calculate Power-to-Weight Ratio

To calculate the power-to-weight ratio, simply input the vehicle's power (hp) and weight (lbs.) and click on the "Calculate" button.

Power-to-Weight Ratio Calculator
Weight lbs.

Understanding the Power-to-Weight Ratio

The power-to-weight ratio (PWR) is a measurement of the ratio of a vehicle's power to its total weight.

There is a positive correlation between a vehicle's PWR and the speed at which it accelerates. That is why motorbikes typically will accelerate at a much quicker pace than cars. Although they are not as powerful, they are lightweight; as such, they have a higher PWR and will accelerate faster.

By calculating a PWR, we can predict the speed at which a vehicle will travel. For instance, if a vehicle has a horsepower of 300 and weighs 3000 pounds, its PWR will be 0.1 hp/lb. This means that it will have a power output of 0.1 hp for every pound in weight.

Determining Power-to-Weight Ratio

It's very straightforward to determine a power-to-weight ratio by dividing the horsepower of a vehicle by its total weight. For instance, if a car weighs 4500 pounds and has a horsepower of 350, the PWR will be as follows:

350 / 4500 = 0.078 hp for every pound of car.

Power-to-Weight Ratio Formula

The formula that is used to determine the power-to-weight ratio of a vehicle is as follows:

PWR = P / W


PWR = Power-to-weight ratio (horsepower per pound, [hp/lb]),
P = Power (horsepower [hp]),
W = Weight (pounds [lb]).

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