What is a gear module?

The gear module is the ratio of the pitch diameter to the number of teeth, representing the unit of size indicating how big or small the gear teeth are.

How is the gear module calculated from the pitch diameter and teeth?

It is calculated using the formula m = d / z, where d is the pitch diameter and z is the number of teeth.

Can I calculate the module if I only know the circular pitch?

Yes, select the 'Module from pitch p' mode and enter the circular pitch; the tool calculates it using m = p / π.

What is the relationship between the module and the addendum?

For standard full-depth teeth, the addendum (h_a) is equal to the module (m).

What units are used for the calculations?

The calculator uses millimeters (mm) for pitch diameter, circular pitch, addendum, and the resulting module.

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Gear Module Calculator

Calculate the gear module m. m = d/z = p/π. Solve the module from the pitch diameter d and tooth count z, or from the circular pitch p. Also returns the pitch diameter, circular pitch and addendum.

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1 examples

d = 100 mm, z = 20 → m = 5 mm

m = d/z = 100/20 = 5 mm. Pitch p = π·m ≈ 15.7080 mm. Addendum h_a = m = 5 mm.

{"result":"Module m = d/z = 100/20 = 5.0000 mm. Pitch diameter d = 100 mm, circular pitch p = π·m = 15.7080 mm, addendum h_a = m = 5 mm.","metadata":{"input":{"mode":"fromDiameter","pitchDiameter":100,"teeth":20},"result":{"module":5,"moduleUnit":"mm","pitchDiameter":100,"teeth":20,"circularPitch":15.708,"addendum":5}}}

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5 options

SettingsAdjust formats, ranges, numbers, and modes.5

Calculation ModeselectOptionalPitch Diameter d (mm)numberOptionalUsed in 'Module from d and z' mode.Number of Teeth znumberOptionalUsed in 'Module from d and z' mode.Circular Pitch p (mm)numberOptionalUsed in 'Module from pitch p' mode.Decimal PlacesnumberOptional

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Gear Module Calculator

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Examples

1. Calculating Module from Pitch Diameter and Teeth

2. Determining Module from Circular Pitch

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