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Power to Weight Ratio Calculator

Power-to-weight ratio in hp/tonne and W/kg, with an estimated 0–100 km/h time.

Enter values

Results update as you type.

Result

Power to weight

107.9 hp/tonne

Watts per kilogram
80.47
Kilograms per horsepower
9.267
Estimated 0–100 km/h
17.47 s
Total weight used
1,390 kg
Category
Family car

The acceleration figure is a rough empirical estimate — traction, gearing and aerodynamics all matter.

About the Power to Weight Ratio Calculator

Power-to-weight ratio in hp/tonne and W/kg, with an estimated 0–100 km/h time.

Also known as: hp per ton, w/kg calculator, power weight ratio, specific power.

How to use this calculator

  1. Enter power, power unit, weight, driver and fuel.
  2. The result updates instantly as you type — press Calculate (or Enter) at any time.
  3. Review the breakdown shown under the main result.
  4. Use Copy result or Share to save the answer or send a link with your inputs.

Formula

ratio = power ÷ total weight

Worked example

Using the values pre-filled in the calculator above:

  • Power = 150
  • Power unit: Horsepower
  • Weight = 1,300 kg
  • Driver and fuel = 90 kg

the calculator returns:

  • Power to weight: 107.9 hp/tonne
  • Watts per kilogram: 80.47
  • Kilograms per horsepower: 9.267
  • Estimated 0–100 km/h: 17.47 s