En Gear Bending Stress Calculator is a free online engineering tool designed to calculate the bending stress of gear teeth based on industry-standard gear design principles. By entering parameters such as transmitted torque, gear module, number of teeth, face width, material properties, and applied load, the Gear Bending Stress Calculator quickly estimates the bending stress acting on the gear tooth root. This helps engineers evaluate gear strength, prevent tooth failure, and optimize gear designs for improved durability and performance. Ideal for mechanical engineers, gearbox designers, and students, this calculator provides fast, accurate, and browser-based calculations without requiring additional software, making gear design and verification more efficient and reliable.

Gear Bending Stress Calculator — Lewis Formula
Drive Input
kW
RPM
N-m
Gear Geometry
mm
—
mm
mm
Material Properties
MPa
SF = σall / σ Safety Factor — Green ≥ 1.5, Orange 1.0–1.5, Red < 1.0
Derived Values
T = — Calculated or direct torque input
d = — Pitch diameter used in force calculation
m / Pd = — Module for Lewis stress (SI)

Awaiting Input

Enter valid parameters to evaluate gear bending safety.

—
Tangential Force (Ft)
—
norte
Lewis Form Factor (Y)
—
dimensionless
Bending Stress (σ)
—
MPa
Safety Factor (SF)
—
σall / σ