Horsepower per pound, per ton and per tonne
HP to Weight Ratio Calculator
Power-to-weight is the shorthand enthusiasts use to compare cars of different sizes. Enter horsepower and weight and see it expressed every common way, from hp per 1,000 lb to hp per tonne.
- HP per US ton (2,000 lb)
- 229 hp
- HP per tonne
- 252 hp
- HP per kg
- 0.252 hp/kg
- Weight per hp
- 8.75 lb/hp
What horsepower-to-weight ratio tells you
The ratio is simply horsepower ÷ weight. A 400 hp, 3,500 lb car has 114.29 hp per 1,000 lb, which is about 252 hp per tonne. Higher is quicker: it predicts acceleration better than horsepower alone, because a lighter car needs less power to go the same pace.
Reference ratios
| hp per tonne | hp per 1,000 lb | Roughly like |
|---|---|---|
| 100 | 45.4 | Small economy car |
| 200 | 90.7 | Hot hatch / sports sedan |
| 300 | 136.1 | Fast sports car |
| 400 | 181.4 | Track-focused supercar |
| 600 | 272.2 | Hypercar or drag build |
Conversions: 1 tonne = 1,000 kg = 2,204.6 lb; a US ton is 2,000 lb.
Link to quarter-mile and 0–60
Because both quarter-mile ET and 0–60 are functions of weight per horsepower, you can turn a ratio into a time. For instance, 8.75 lb/hp is about 12.00 s over the quarter. Try the quarter mile calculator or the 0–60 calculator.
Frequently asked questions
How do you calculate the horsepower to weight ratio?
Divide horsepower by weight. To express it per 1,000 lb, multiply the result by 1,000.
What is a good hp per ton?
Around 200 hp per tonne is quick for a road car, 300 is strongly sporty and 400+ is supercar level.
What is the difference from power-to-weight in W/kg?
It is the same idea in SI units. See the power to weight ratio calculator.
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