How do I calculate torque from horsepower?

Use torque in lb-ft = horsepower x. The result applies at that RPM, not across the whole power curve.

Is peak torque enough to compare engines?

No. RPM range, gearing, vehicle weight, throttle response and the full torque curve matter.

Why show N-m and lb-ft?

U.S. specs commonly use lb-ft, while many international specifications use newton-meters.

Engine Torque Calculator

Calculate engine torque from horsepower and RPM, or convert torque between lb-ft, N-m and kgf-m.

Power

Power unit

Engine speed (RPM)

Calculate torque from horsepower and RPM

The English calculator intent is usually the classic horsepower, RPM and torque relationship. For U.S. vehicle specs, lb-ft is the primary torque unit, with N-m shown for international comparison.

T or q u e_{l b - f t} = \frac{H or se p o w er \times 5252}{R P M}

T or q u e_{N - m} = \frac{k W \times 9549}{R P M}

1 l b - f t = 1.355818 N - m

Frequently Asked Questions

Sources and References

Calculations are based on the listed reference sources. Links open in a new tab.

Updated: June 2, 2026

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