Wheel Torque Calculator
Wheel torque is the turning force that actually reaches the drive wheels and accelerates a vehicle, after the engine's output has passed through the gearbox and final drive. Because the drivetrain trades rotational speed for torque, the force at the wheels is much larger than the torque the engine produces, particularly in lower gears. This calculator finds wheel torque from three inputs: engine torque, the selected transmission gear ratio, and the final drive (axle) ratio. The method is direct: wheel torque equals engine torque multiplied by the gear ratio and then by the final drive ratio. You enter the engine torque in pound-feet along with the two ratios, and the tool returns the torque at the wheels, computed deterministically from the formula shown below, never estimated, so the worked example reconciles exactly with the result on screen. Lower gears carry larger numerical ratios, which is why a vehicle pulls hardest in first gear and why low-range gearing helps with climbing and towing. This figure is the ideal wheel torque from gearing alone and does not subtract drivetrain friction losses, typically around 10 to 15 percent. Use this tool to compare gearing choices or to estimate the force available at the wheels in any gear.
Wheel torque is engine torque x gear ratio x final drive ratio. For 200 lb-ft of engine torque, a gear ratio of 3.50 and a final drive of 3.73, the wheel torque is 2,611.00 lb-ft.
Wheel torque formula
wheel torque = engine torque x gear ratio x final drive ratio
engine torque = crank torque in lb-ft
gear ratio = transmission ratio in the selected gear
final drive ratio = axle (differential) ratio
The transmission and final drive multiply engine torque by their combined ratio. The product is the ideal torque delivered to the wheels, before any drivetrain friction losses are subtracted.
Worked example
An engine makes 200 lb-ft, the gear ratio is 3.50 and the final drive is 3.73.
- Total drive ratio = 3.50 x 3.73 = 13.055
- Wheel torque = 200 x 13.055 = 2,611.00 lb-ft
The wheel torque is 2,611.00 lb-ft. These are the calculator's default inputs, so the result above matches the widget exactly.
Wheel torque: frequently asked questions
What is wheel torque?
Wheel torque is the turning force delivered to the drive wheels after the engine's output has been multiplied through the transmission and final drive. It is what actually accelerates the vehicle. Because gearing multiplies torque, wheel torque is much higher than engine torque, especially in lower gears.
How is wheel torque calculated?
Multiply the engine torque by the transmission gear ratio and then by the final drive ratio. The drivetrain trades speed for torque, so each reduction ratio greater than one increases the torque reaching the wheels. This calculator uses engine torque times gear ratio times final drive ratio.
Why is wheel torque higher in low gears?
Lower gears have larger numerical ratios, which multiply engine torque more. That is why a vehicle pulls hardest in first gear and why low-range gearing helps with steep climbs and towing. As you shift up, the ratio falls, wheel torque drops, and road speed rises for the same engine speed.
Does this account for drivetrain losses?
No. This is the ideal wheel torque from the gear ratios alone. Real drivetrains lose some torque to friction in the gearbox, differential and bearings, often around 10 to 15 percent. To estimate torque actually at the tire, multiply the result by a drivetrain efficiency factor.
How does wheel torque relate to tractive force?
Dividing wheel torque by the loaded tire radius gives the forward force pushing the vehicle, the tractive force. Larger tires reduce that force for the same torque, while smaller tires increase it, which is one reason gearing is often changed when tire size changes.
Official sources
- Vehicle drivetrain and performance reference: US National Highway Traffic Safety Administration (NHTSA). As at 25 June 2026.
Reviewed by the CalculatorHub team, edited by James Graham, 25 June 2026. See our methodology. This is general information, not financial, tax, legal or investment advice.