Estimate your car’s 0-60 mph and 0-100 km/h time from horsepower, weight, and drivetrain, or find the power needed for a target time.
0-60 Time Formula
The calculator estimates acceleration from the ratio of vehicle weight to engine power. To estimate a 0-60 mph time, it uses this empirical formula:
t = K * (W / P)^{0.8}
To find the power needed for a target 0-60 time, it rearranges the same relationship:
P = W / (t / K)^{1.25}
Variables:
- t is the estimated 0-60 mph time, in seconds
- W is the vehicle weight in pounds, including the driver and fuel
- P is the crank (engine) horsepower
- K is a launch constant that accounts for drivetrain traction: 0.70 for AWD, 0.76 for RWD, and 0.80 for FWD
Pick what you want to find at the top of the calculator. In “Estimate my 0-60 time” mode you enter your car’s weight and power and the tool returns an estimated 0-60 mph and 0-100 km/h time. In “Power needed for a target 0-60” mode you enter a target time and the tool returns the crank and wheel horsepower required. If you enter wheel horsepower instead of crank horsepower, the calculator converts it using a typical drivetrain loss of 15% for RWD, 20% for AWD, and 12% for FWD.
The exponent of 0.8 reflects that acceleration is not perfectly proportional to power-to-weight: heavier, more powerful cars lose proportionally more time to traction and aerodynamic drag, while very light cars gain less than the raw ratio suggests.
Estimated 0-60 Times by Power-to-Weight Ratio
This table shows estimated 0-60 mph times for common weight-to-power ratios. Find your ratio by dividing curb weight plus driver (in pounds) by crank horsepower.
| Weight-to-power (lbs/hp) | AWD | RWD | FWD |
|---|---|---|---|
| 5 lbs/hp | 2.5 s | 2.8 s | 2.9 s |
| 6 lbs/hp | 2.9 s | 3.2 s | 3.4 s |
| 8 lbs/hp | 3.7 s | 4.0 s | 4.2 s |
| 10 lbs/hp | 4.4 s | 4.8 s | 5.0 s |
| 12 lbs/hp | 5.1 s | 5.6 s | 5.8 s |
| 14 lbs/hp | 5.8 s | 6.3 s | 6.6 s |
| 16 lbs/hp | 6.4 s | 7.0 s | 7.4 s |
| 20 lbs/hp | 7.7 s | 8.3 s | 8.8 s |
| 25 lbs/hp | 9.2 s | 10.0 s | 10.5 s |
Example Problems
Example 1: Estimate a 0-60 time.
Your RWD car weighs 3,400 lbs with you in it and makes 300 crank horsepower. The weight-to-power ratio is 3400 / 300 = 11.33 lbs/hp. Applying the formula:
t = 0.76 * (11.33)^0.8 = 0.76 * 6.97 = 5.3 seconds, with an estimated 0-100 km/h time of about 5.6 seconds.
Example 2: Find the power needed for a target time.
You want a 4.0-second 0-60 in a 3,500 lb AWD car. Rearranging the formula:
P = 3500 / (4.0 / 0.70)^1.25 = 3500 / 8.84 = 396 crank horsepower, which is about 317 wheel horsepower after a typical 20% AWD drivetrain loss.
Frequently Asked Questions
How accurate is a 0-60 time estimated from horsepower and weight?
Power-to-weight is the single biggest predictor of acceleration, so the estimate usually lands within a few tenths of a second of published times for a well-driven car. Launch technique, tire grip, gearing, shift speed, and surface conditions account for most of the remaining difference. Cars with launch control and sticky tires beat the estimate; cars with tall gearing or poor traction fall short of it.
Why does drivetrain type change the estimate?
The first second of a 0-60 run is traction-limited, not power-limited. AWD cars put power down almost immediately, so they run quicker times from the same power-to-weight ratio, while FWD cars lose the most time to wheelspin and weight transfer off the line. The calculator captures this with a different launch constant for each layout.
Should I enter crank horsepower or wheel horsepower?
Either works, as long as you pick the matching option. Manufacturer ratings are crank horsepower, while dyno results are usually wheel horsepower. The calculator converts wheel figures to crank figures internally using a typical loss for your drivetrain, so a dyno number gives a slightly more realistic estimate of what your specific car will do.
