Power to Weight Ratio Calculator

Power to Weight Ratio Calculator is an easy to use tool to calculate the Power to Weight Ratio of a vehicule.
the Power to Weight Ratio is a measure of how much power the vehicle can produce per unit weight. To be able to calculate the Power to Weight Ratio the user should know the power and the weight of their vehicule, the user can find these values in the vehicule manual or also online.

PWR Calculator contain three inputs and a unit select for each input:

Power: The power of the vehicule and the provided units are Watts (W), KiloWatts (kW), Mechanical horsepowers (hp(l)) and Metric horsepowers (hp(M)).
Weight: The weight of the vehicule and the provided units are Kilogram (kg) and Pounds (lb)
PWR: The Power to Weight Ratio of the vehicule and the provided units are Watts per kilogram (W/kg), KiloWatts per kilogram (kW/kg), Mechanical horsepower per pound (hp(l)/lb) and Mechanical horsepower per kilogram (hp(l)/kg)

Beside calculating the PWR this tool can also calculate:

The Power if the user enter the Weight and PWR values
The Weight if the user enter the Power and PWR values

How to Calculate the PWR manually

To calculate the Power to Weight Ratio manually we should divide the vehicle's power by its weight.
PWR formula:
PWR = Power / Weight
We should be careful with units to get the right PWR value, some of the most common PWR units are power-to-weight ratio units are horsepower per pound (hp/lb) and kilowatt per kilogram (kW/kg). so if we are about to calculate the PWR and we want that the unit of the PWR be horsepower per pound (hp/lb) the unit of the power should be Mechanical horsepowers (hp(l)) and the unit of the weight should be pounds (lb).

Example 1
The power of the vehicule is 150 Mechanical horsepowers (hp(l)) and the weight of the vehicule is 3000 Pounds (lbs).
To calculate the PWR in Mechanical horsepower per pound (hp(l)/lb) we use the formula:
PWR = 150 / 3000 = 0.05 hp(l)/lb

Example 2
The power of the vehicule is 200 Metric horsepowers (hp(l)) and the weight of the vehicule is 1700 kilograms (kg).
To calculate the PWR in KiloWatt per kilogram (kW/kg) we use should first convert the power to kiloWatts (kW):
200 hp(l) = 200 * 0.735499 kW = 147.198 kW
Then we use the formula:
PWR = 147.198 / 1700 = 0.0865 kW/kg

You can also calculate the Power using the weight and the PWR values using this Formula:
Power = PWR * Weight
And you can calculate the Weight using this formula:
Weight = Power / PWR

Using the right units is important when calculating PWR, Power or Weight manually