Gears
Gear Outside Diameter Calculator
Enter module and tooth count to estimate the tip diameter of a standard, non-profile-shifted external spur gear.
Inputs
Formula
Standard external spur-gear tip diameter
Worked example
Using the default values shown in the calculator, the same formula gives the following result. This is a quick sanity check for the calculation, not a design recommendation.
Inputs
- Module
- 2 mm
- Number of teeth
- 30 teeth
Result
- Outside diameter
- 64 mm
Related calculators
Continue your workflow with a related calculation.
Gears
Gear Pitch Diameter Calculator
Calculate standard metric spur-gear reference diameter from module and number of teeth.
Gears
Gear Module Calculator
Find the metric module that matches a measured or specified spur-gear reference diameter and tooth count.
Gears
Gear Center Distance Calculator
Calculate center distance for two standard external spur gears from module and tooth counts.
Technical references for this calculation
Frequently asked questions
When is z + 2 valid?
It is the standard external spur-gear result when addendum equals one module and there is no profile shift.
Is this valid for internal or profile-shifted gears?
No. Those geometries use different tip-diameter relationships.