How to use the Horsepower Calculator
The horsepower calculator estimates a car's power from its weight and quarter-mile time.
Open the Horsepower Calculator →
What you need to enter
- Weight with driver (lb)
- Quarter-mile time (s)
The formula
hp ≈ weight ÷ (time ÷ 5.825)³.
Worked example
Using the default values in the calculator:
- Weight with driver (lb): 3300
- Quarter-mile time (s): 13.5
| Estimated horsepower | 265 hp |
Tips for better results
- It is only an estimate.
- Traction and weather affect times.
Common mistakes to avoid
- Using the wrong weight.
- Expecting dyno accuracy.
Please note: Results are estimates for general use. For safety-critical work such as electrical or building projects, check with a qualified professional and local codes. See our Disclaimer.