Torque to Horsepower Calculator

What Is a Torque to Horsepower Calculator?

Torque and horsepower are two different ways of describing an engine's output, and they're linked by RPM. This calculator uses the standard automotive/engineering formula to convert one to the other at a given RPM: fill in torque and RPM to find horsepower, or fill in horsepower and RPM to find torque.

This is the exact relationship printed on every dyno chart, where the torque curve (in lb-ft) and horsepower curve always cross at precisely 5,252 RPM.

How to Read Your Results

Horsepower (from Torque & RPM)

This shows the horsepower produced when your entered torque figure is delivered at your entered RPM — the standard way dyno sheets calculate a horsepower curve from measured torque.

Torque (from HP & RPM)

This shows the torque required to produce your entered horsepower figure at your entered RPM — useful when a spec sheet only lists peak horsepower and you want to back-calculate torque.

Crossover Point

A fixed reference: torque (lb-ft) and horsepower numbers are mathematically equal at exactly 5,252 RPM, regardless of the engine. Below that RPM, the torque number is higher; above it, horsepower is higher.

Real-World Example

An engine produces 350 lb-ft of torque at 4,500 RPM. How much horsepower is that?

Using HP = (350 × 4,500) ÷ 5,252 gives approximately 300 horsepower at that RPM point.

Tips for Working With Torque and Horsepower

• This is a single-RPM calculation, not a full power curve — real engines produce different torque at every RPM.
• Peak torque and peak horsepower usually occur at different RPMs — check both figures on a spec sheet, not just one.
• Diesel and electric motors typically deliver high torque at low RPM, which is why they feel strong from a stop.
• The 5,252 constant is fixed and universal — it applies to any engine, motor, or rotating shaft measured in lb-ft and RPM.

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Last updated: August 2026 · Reviewed by: Simple Calculator Tools Editorial Team