Trip estimates

Engine Horsepower Calculator

Estimate engine horsepower from quarter-mile elapsed time and vehicle weight using the Hale ET method. Use this Travel and transport tool to enter your numbers, review the result, and understand the key assumptions before making the next decision.

What you get
A focused calculator, clear explanation, common questions, and useful next tools.
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Result
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How this calculator works
The result depends on the numbers you enter and the assumptions shown below.

Estimated HP = Weight ÷ (ET / 5.825)³. This formula by Patrick Hale estimates wheel horsepower from drag strip elapsed time and vehicle weight. Results are estimates and vary by traction, conditions, and drivetrain losses.

Review the inputs carefully and treat the output as an estimate. For decisions involving money, taxes, health, law, or security, compare the result with trusted professional guidance when needed.

Frequently asked questions

How accurate is the ET method?

It provides a reasonable estimate for drag-prepared vehicles but can be off for street cars due to launch technique, traction, and drivetrain efficiency differences.