# Power To Weight Ratio Calculator

Enter the power of your engine and the total weight of your vehicle to calculate the power-to-weight ratio (PWR).

## Power To Weight Ratio Calculator:

Use this power to weight ratio calculator to understand the true performance potential of your vehicle, machine, or even yourself as a cyclist. The calculator is a helpful option for comparing the power (ability to do work) of something to its weight (mass).

## Power-To-Weight Ratio & Why to Use:

The power-to-weight ratio is a measurement that helps to compare the power output of a machine (like an engine or motor) in relation to its weight. It's a key metric used to evaluate the performance of many things, including vehicles, athletes, and aircraft. Generally, a higher power-to-weight ratio indicates better acceleration and handling. It is also used by cyclists to assess their fitness level.

Here's why it's important:

• Helps to Compare Performance: It is very helpful in comparing the acceleration potential of different vehicles (cars, motorcycles, bicycles) or machines. For instance, if there are two cars and both of them have the same horsepower. Now the car that will have less weight will have a high PWR value. Meanwhile, the less heavy car will have a good performance comparatively. Find the ratio for the given horsepower (hp) of an engine and the weight of a vehicle with the hp to weight ratio calculator.
• Analyzes Efficiency and Power Usage: The calculation of power to weight ratio helps to identify the efficient use of power to move the weight. A high PWR value means a lighter system, which means lower energy and fuel consumption. A strong cyclist with a good PWR rating can push his weight with more ease while going uphill. PWR is not the sole indicator of energy consumption. Aerodynamics and drivetrain efficiency also play a role.

By understanding PWR, you can make informed decisions when choosing equipment or training strategies to improve your cycling performance. A power-to-weight ratio calculator can be a valuable tool in this process. Keep in mind that PWR is a calculated value, and factors like friction and air resistance can affect it.

## How To Calculate Power To Weight Ratio?

Follow these three simple steps to calculate PWR:

### Step #1: Find Power Output:

Determine the power output of the object or vehicle. Keep in mind that units can vary but the most common units that are used are horsepower (hp) for engines or watts (W) for motors. You can find the power output on the user manual, or product specification sheet or can search online.

### Step #2: Calculate The Weight

Weigh your object or vehicle. Pounds (lb) or kilograms (kg) are the two common units that are used to measure weight. For vehicles, curb weight(weight of the vehicle without passengers or cargo) is used.

### Step #3: Use The Power-To-Weight Ratio Formula

PWR =$$\frac{Power}{Weight}$$

Alternatively: Our power to weight ratio calculator also uses these pre-defined formulas to convert your inputs into a meaningful hp to weight ratio, so that you can have a deeper understanding of your system or vehicle's performance.

### Solved Examples (Power-To-Weight Ratio):

1 . Calculate the power-to-weight ratio of a car with a weight of 3,000 pounds and an engine power of 350 horsepower.

Solution:

Given that:

• Car Weight = 3000 pounds
• Power = 350 Hp

By adding values in the power-to-weight ratio (PWR) formula:

=$$\frac{350}{3000}$$

= 0.11667 (hp(l)/lb)

2. Find power to weight ratio of a cyclist who weighs 60 kg and can sustain a power output of 210 watts.

Solution:

Given that:

• Cyclist Weight = 60 kg
• Power = 210 Watts

Put values in the power-to-weight ratio formula:

=$$\frac{210}{60}$$ = 3.5 W/Kg

To quickly get the PWR values, use the power to weight calculator.

### Power To Weight Ratio Chart:

 Weight 120W 150W 180W 210W 240W 270W 300W 330W 360W 390W 45kg 2.7 3.3 4.0 4.7 5.3 6.0 6.7 7.3 8.0 8.7 50kg 2.4 3.0 3.6 3.8 4.8 5.4 6.0 6.6 7.2 7.8 55kg 2.2 2.7 3.3 3.5 4.4 4.9 5.4 6.0 6.5 7.1 60kg 2.0 2.5 3.0 3.2 4.0 4.5 5.0 5.5 6.0 6.5 65kg 1.8 2.3 2.8 3.0 3.7 4.1 4.6 5.0 5.5 6.0 70kg 1.7 2.1 2.6 2.8 3.4 3.8 4.3 4.7 5.1 5.6 75kg 1.6 2.0 2.4 2.6 3.2 3.6 4.0 4.4 4,8 5.2 80kg 1.5 1.9 2.2 2.5 3.0 3.4 3.8 4.1 4.5 4.9 85kg 1.4 1.8 2.1 2.3 2.8 3.2 3.5 3.9 4.2 4.6 90kg 1.3 1.7 2.0 2.2 2.7 3.0 3.3 3.7 4.0 4.3 95kg 1.2 1.5 1.9 2.0 2.5 2.8 3.2 3.5 3.8 4.1

## FAQs:

### What Is A Good Power To Weight Ratio of A Car?

• 20 lbs per HP: This is a good range for daily-use cars. Most everyday cars fall in this range as they offer better fuel economy
• 10 lbs/HP: It includes sporty sedans, efficient hatches, and performance-oriented SUV’s
• 8 lbs/HP: A car having this power-to-weight ratio is considered a fast car, with a strong acceleration capability. However, even lower car power-to-weight ratios can be very fast, especially for lightweight, high-performance cars

### Which Motor Has the Highest Power-To-Weight Ratio?

It depends on the specific application and motor design. However, permanent magnet motors are generally considered to have the highest power-to-weight ratio because of their high torque, density, and relatively lightweight construction.

### Does Power-To-Weight Ratio Determine Acceleration?

The car power to weight ratio helps to know how fast a car can accelerate. While PWR is a crucial factor, it's not the only thing that determines acceleration.

References:

From the source of Wikipedia: Power-to-weight ratio, Physical interpretation, Propulsive power

From the source of Jteach.org: Calculating Power to Weight Ratio, When Performance Matters