Mechanical Design

Torque Calculator

Convert between power, speed, and torque — useful for shaft design, coupling selection, gearbox sizing, and motor selection.

Inputs

Torque

Torque

—

in·lb

Torque

—

ft·lb

Torque

—

N·m

Inputs

Power

Power

—

hp

Power

—

kW

Power

—

W

Power — Speed — Torque

T (in·lb) = (HP × 63,025) / RPM T (N·m) = P (W) / ω   where ω (rad/s) = RPM × 2π / 60 P (W) = T (N·m) × ω (rad/s) P (hp) = T (in·lb) × RPM / 63,025
T = torque P = power ω = angular velocity (rad/s) 1 hp = 745.7 W 1 ft·lb = 12 in·lb = 1.3558 N·m