Quarter Mile Time
Estimate quarter-mile elapsed time and trap speed from power.
About Quarter Mile Time
Quarter-mile performance follows a rough cube-root rule in the weight to power ratio, producing elapsed time and an estimated trap speed. These approximations assume good traction and perfect launching, so they are ballpark figures rather than guarantees of real drag-strip performance.
Formula
Quarter Mile Time
ET ~ 6.269 x (weight / hp)^(1/3); trap ~ 234 x (hp / weight)^(1/3)
- trap speed
- Speed measured across the finish line
Worked example
With the default values below, Quarter Mile Time returns Elapsed Time of 12.54. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Vehicle weightminimum 1 lb
- 3,200 lb
- Horsepowerminimum 1
- 400
Results
- Elapsed Time
- 12.54 s
- Trap Speed
- 117.0 mph
- Power-to-Weight (hp/ton)
- 250.0
Step by step
- 1Values used
- 2Quarter Mile Time
- 3Elapsed Time= 12.54 s
- 4Trap Speed= 117.0 mph
- 5Power-to-Weight (hp/ton)= 250.0
Assumptions and limits
- The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
- Estimates assume favorable traction and shifting; real results depend on tires, drivetrain losses and weather.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Estimates assume favorable traction and shifting; real results depend on tires, drivetrain losses and weather.
Frequently Asked Questions
How is Quarter Mile Time calculated?
ET ~ 6.269 x (weight / hp)^(1/3); trap ~ 234 x (hp / weight)^(1/3) Quarter-mile performance follows a rough cube-root rule in the weight to power ratio, producing elapsed time and an estimated trap speed.
Why does Quarter Mile Time matter?
These approximations assume good traction and perfect launching, so they are ballpark figures rather than guarantees of real drag-strip performance.
What values do I need to enter?
This calculator takes 2 inputs: Vehicle weight, Horsepower. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.