Calculator
Power-to-Weight Calculator
Calculate a car's power-to-weight ratio in hp per tonne, kg per hp, lb per hp and W/kg, and see where it sits from economy car to hypercar.
Each horsepower carries 5.0 kg. Class: Hot hatch / sports saloon.
Grey bars are the nearest cars from our checked spec sheets; each links to its page.
Why power-to-weight matters more than power
Acceleration is force divided by mass, so a light car with modest power can out-accelerate a heavy one with much more. A 1,100 kg hot hatch with 300 hp has about 270 hp per tonne; a 2,300 kg SUV needs 620 hp to match it.
Rough scale
- Under 120 hp/t — economy car
- 120–200 hp/t — brisk everyday car
- 200–300 hp/t — hot hatch or sports saloon
- 300–450 hp/t — sports car
- 450–700 hp/t — supercar
- 700+ hp/t — hypercar
Use kerb weight with a driver (about +75 kg) for figures that match the road.
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