How to use: Enter any two of Power, Torque, or Speed. Leave one field blank (or zero) — it will be calculated automatically.
Power (P)
Torque (T)
Speed (n)
RPM

Pitch Circle Diameter — for force calculation
mm
Pressure Angle (α)

Formulas

Torque from PowerT = P×9549.3 / n (kW, RPM)
Power from TorqueP = T×n / 9549.3 (kW)
Speed from P & Tn = P×9549.3 / T
Angular Velocityω = 2πn / 60 (rad/s)
Tangential ForceFt = 2T×1000 / d (N)
Radial ForceFr = Ft × tan(α)
1 HP= 0.7457 kW
Power – Torque – Speed Triangle
Power (kW)
kilowatts
Power (HP)
horsepower
Torque (N·m)
Newton-metres
Speed (RPM)
rev/min
Torque in Other Units
kgf·m
kilogram-force metre
lb·ft
pound-force foot
lb·in
pound-force inch
Angular Vel. (ω)
rad/s
Gear Forces at PCD
Tangential Force (Ft)
N  (driving force)
Radial Force (Fr)
N  (separating force)
Normal Force (Fn)
N  (along tooth normal)
PCD used
mm
Forces shown only when PCD is entered. Tangential force = driving force at pitch circle. Radial force acts along the line of centres. Normal force acts perpendicular to tooth face.