Enter the power and weight of a car or machine to calculate the power-to-weight ratio of that device.

Power-to-Weight Ratio Formula

The following formula is used by the calculator above to determine the power-to-weight ratio of a car of the system.

PTW= P / W
  • Where PTW is the power to weight ratio
  • P is power, typically expressed in horsepower
  • W is weight, typically expressed in lbs or kgs

In the case of a ratio, the most important thing to keep in mind is to make sure units are consistent in the end results. For this, the power can be any unit of power, and the same goes for weight, as long as the power-to-weight ratio is expressed in those same units. The better the power-to-weight ratio of a car, the better it typically performs on a straight line and track. A car with a poor power-to-weight ratio will likely be slow and sluggish around corners.

Power to Weight Ratio Definition

Power to weight ratio is a measure of how much power a vehicle or machine has in relation to its weight. It helps determine the overall performance and efficiency of the vehicle or machine by indicating how much power is available for each unit of weight.

How to calculate power to weight ratio?

How to calculate power to weight ratio?

  1. First, measure the power output.

    Most typically this is the total engine power output of a car or system.

  2. Next, measure the weight.

    Measure the weight of the object or the system.

  3. Finally, calculate the power to weight ratio.

    Calculate the ratio using the formula above.


What factors can affect the power-to-weight ratio of a vehicle?

The power-to-weight ratio can be affected by several factors including the vehicle’s engine size, the materials used in its construction, and any additional weight such as passengers or cargo. Modifications to increase engine power can also improve the ratio.

How does the power-to-weight ratio influence a vehicle’s performance?

A higher power-to-weight ratio generally means a vehicle can accelerate faster and perform better, especially in terms of speed and agility. It’s a critical factor for performance vehicles and racing cars, where quick acceleration and the ability to maintain high speeds are essential.

Can the power-to-weight ratio be improved in existing vehicles?

Yes, the power-to-weight ratio can be improved by either increasing the power output of the vehicle, such as through engine modifications or tuning, or by reducing the weight of the vehicle. This can involve removing unnecessary parts, using lighter materials, or both.

Why is it important to use consistent units when calculating the power-to-weight ratio?

Using consistent units ensures the accuracy of the power-to-weight ratio calculation. Mixing different units for power and weight can lead to incorrect results, which could misrepresent the vehicle’s actual performance capabilities. It’s crucial to convert all measurements to the same unit system before performing the calculation.

power to weight ratio calculator
power to weight ratio formula