Torque Calculator

The Twisting Force Behind Every Launch

Torque is what actually accelerates a vehicle off the line and pulls a load up a grade — horsepower is derived from it, not the other way around. This calculator solves for torque two ways: backward from a known horsepower and RPM figure, or directly from a force applied at a known lever arm distance, which is the definition of torque in its purest mechanical form.

The Formula

The force-and-distance form is the fundamental physical definition of torque; the power-and-RPM forms are algebraic rearrangements of the horsepower formula, useful when only a power rating is known.

Where This Matters

• Towing and hauling capacity — torque at low RPM is the figure that determines how well a vehicle gets a heavy trailer moving from a stop.
• Fastener specifications — the force-and-distance form is exactly how torque wrench specs work: a bolt's tightening spec is a torque value derived from a known force at a known wrench length.
• Reverse-engineering a spec sheet — manufacturers sometimes publish horsepower and RPM without listing peak torque directly; this calculator recovers it.
• Comparing engine character — an engine that produces its torque peak at low RPM feels stronger in everyday driving even if its horsepower peak is unremarkable.

Torque Required at Various RPM, 300 HP Constant

Computed directly from Torque = (HP × 5252) ÷ RPM at a constant 300 HP; note torque falls as RPM rises for a fixed power output.

How to Use This Calculator

1. Choose calculation mode: From Power & RPM, or From Force & Lever Arm.
2. Select Imperial or Metric units for the chosen mode.
3. Enter power and RPM (or force and lever arm distance).
4. Select Calculate to see the resulting torque value.

Related Calculations

Convert the result into horsepower with the Horsepower Calculator, or use the dedicated Torque to Horsepower Calculator for a direct one-way conversion.