Engine Horsepower Calculator

The Engine Horsepower Calculator determines estimated vehicle power through two methods: elapsed time (ET) in a quarter mile or final trap speed achieved. Perfect for automotive enthusiasts, engine builders, drag racers, and owners who want to know their engine's real performance based on practical acceleration tests and track performance data.

Updated at: 12/16/2025

Engine Horsepower Calculator

The Engine Horsepower Calculator determines estimated vehicle power through two methods: elapsed time (ET) in a quarter mile or final trap speed achieved. Perfect for automotive enthusiasts, engine builders, drag racers, and owners who want to know their engine's real performance based on practical acceleration tests and track performance data.

Time in seconds to travel 402.3 meters (1/4 mile)

ET Method (Elapsed Time)

Uses vehicle weight and time to complete 1/4 mile (402.3m). Most accurate method for track-tested vehicles.

HP = Weight ÷ (ET ÷ 5.825)³

Trap Speed Method

Uses vehicle weight and maximum speed reached at the end of 1/4 mile run.

HP = Weight × (Speed ÷ 234)³

Important Notes

  • Weight should include vehicle, driver, passenger, and significant equipment.
  • Results are estimates based on widely accepted empirical formulas.
  • For greater accuracy, use data obtained from official drag strip.
  • Track conditions, temperature, and altitude can affect actual results.