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Power-to-Weight Ratio Calculator

HP/ton, kW/kg — and a 0-100 km/h estimate.

Power-to-weight
200.0 hp/ton(0.149 kW/kg)
hp/lb
0.0907
Power (hp)
300.0
Weight (kg)
1500
Rough 0-100 km/h
~7.3 s

Spirited family car. Capable without being scary.

About this calc

The single best predictor of acceleration. Enter power and weight; get the ratio in multiple units plus a rough 0-100 km/h estimate.

FAQ

Why is power-to-weight more useful than just horsepower?
Because the same engine in a lighter car accelerates harder. A 300 hp Miata would dust a 300 hp truck. P/W is what actually predicts performance.
Should I include driver weight?
Yes — add 75-80 kg for the driver. Manufacturer specs quote kerb weight (empty), but real-world acceleration happens with a body in the seat.
How accurate is the 0-100 estimate?
Rough — within a second or two for typical RWD/AWD cars. Launch technique, traction, and transmission type (DCT vs manual vs auto) can easily shift the real number.