Calculate 1/4 Mile Times

1/4 Mile Performance Calculator

Include driver and fuel weight.

Preferably Wheel Horsepower (WHP).

Estimated Results

Elapsed Time (ET) 0.00 seconds

Trap Speed 0.00 MPH

*Results are estimates based on ideal traction and sea-level atmospheric conditions.

function calculateQuarterMile() { var weight = parseFloat(document.getElementById('vehicleWeight').value); var hp = parseFloat(document.getElementById('wheelHP').value); var resultDiv = document.getElementById('performanceResult'); if (isNaN(weight) || isNaN(hp) || weight <= 0 || hp <= 0) { alert("Please enter valid positive numbers for both Weight and Horsepower."); return; } // Using the industry standard Hale's Formula // ET = 6.269 * (Weight / HP)^(1/3) // Speed = 234 * (HP / Weight)^(1/3) var et = 6.269 * Math.pow((weight / hp), 1/3); var speed = 234 * Math.pow((hp / weight), 1/3); document.getElementById('displayET').innerHTML = et.toFixed(2); document.getElementById('displaySpeed').innerHTML = speed.toFixed(2); resultDiv.style.display = 'block'; }

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Understanding 1/4 Mile Performance Metrics

Whether you are a professional drag racer or a weekend enthusiast, predicting your vehicle's performance at the drag strip is essential. Our 1/4 Mile Time Calculator uses physics-based formulas to estimate your Elapsed Time (ET) and Trap Speed based on the two most critical variables: weight and power.

The Power-to-Weight Ratio

In drag racing, the power-to-weight ratio is king. A lighter car requires less energy to accelerate, while more horsepower provides the thrust needed to overcome inertia and aerodynamic drag. For example, a 2,500 lbs car with 300 HP will often outperform a 4,000 lbs car with 400 HP because it has a superior power-to-weight ratio.

WHP vs. Crank HP

For the most accurate results in our calculator, you should use Wheel Horsepower (WHP). Wheel horsepower is the actual power measured at the drive wheels after accounting for drivetrain loss (typically 15-20% for automatics and 10-15% for manuals). If you only know your manufacturer's rated HP (Crank HP), subtract approximately 15% for a more realistic estimation.

Typical 1/4 Mile Benchmarks

Vehicle Category	Typical ET (Sec)	Typical Speed (MPH)
Economy Sedan	16.0 – 18.0	75 – 85
Modern Sport Compact	13.5 – 14.5	95 – 105
Muscle Cars / Performance EVs	11.0 – 12.5	110 – 125
Supercars	9.5 – 10.5	130 – 145

Factors That Affect Your Real-World Time

While this calculator provides a mathematically "perfect" run, several real-world factors will influence your actual slip at the track:

• Traction (The Launch): Your 60-foot time is crucial. Spinning the tires can add seconds to your ET even if your trap speed remains high.
• Density Altitude (DA): Engines make less power in hot, humid, or high-altitude conditions. Cold, dry air is "fast" air.
• Transmission & Gearing: Modern dual-clutch transmissions shift faster than humans, leading to better ETs than a manual with the same power.
• Aerodynamics: At speeds over 100 MPH, wind resistance becomes a major factor that simple HP/Weight formulas don't fully capture.

Calculation Example

If you have a car weighing 3,400 lbs (including driver) and it produces 400 WHP:

1. The weight-to-power ratio is 8.5 lbs per HP.
2. The cube root of 8.5 is approximately 2.04.
3. Multiplying 2.04 by the ET constant (6.269) results in an ET of 12.79 seconds.
4. The estimated trap speed would be approximately 114.6 MPH.