This Involute Spline Calculator helps mechanical engineers design and analyse spline connections based on ANSI B92.1, DIN 5480, and ISO 4156 standards.
You can quickly calculate:
- Spline geometry (pitch, major, minor diameter)
- Torque capacity
- Shear and bearing stress
- Safety factor
- Shaft weakening effect
This tool is useful for machine design, shaft coupling design, and power transmission analysis.
Mechanical Design Tool
Involute Spline Calculator
Geometry · Torque Capacity · Stress Analysis · Shaft Weakening
01Input Parameters
Standard & System
Geometry
Diametral Pitch (Pd)teeth/in
T/in
Number of Teeth (N)integer
teeth
Pressure Angle (α)
Engagement Length (L)inch
in
Root Form
▾
Shaft Material
▾
Applied Torque (T)N·m
N·m
Target Safety Factor
—
02Spline Geometry
Pitch Diameter (d)
—mm
Major Dia — Shaft (D_e)
—mm
Minor Dia — Shaft (d_e)
—mm
Base Circle (d_b)
—mm
Tooth & Space Dimensions
Circular Pitch—mm
Tooth Thickness—mm
Tooth Depth—mm
Addendum—mm
Dedendum—mm
Hub Bore—mm
03Stress Analysis
Shear Stress (τ)
—MPa
IdleBearing Stress (σ_b)
—MPa
IdleGoverning Safety Factor
—SF
IdleCalculate to see design recommendation.
04Shaft & Design Results
Shaft Weakening—ratioe_w = (d_min / d_pitch)^3
Polar Section Modulus—mm³Effective torsional section modulus
Tangential Force—NF_t = 2T / d_pitch
Min Length for Target SF—mmRequired engagement length
Frequently Asked Questions (FAQ’s)
What is an involute spline?
An involute spline is a mechanical shaft connection with teeth designed using involute profiles for smooth torque transmission.
Which standard is best: ANSI, DIN or ISO?
ANSI is common in the US, DIN in Europe, and ISO is globally accepted.
What is safety factor in spline design?
It ensures the spline can handle loads without failure.
How is torque calculated in splines?
Torque depends on tooth geometry, material strength, and engagement length.