Gear Span Calculator

This calculator provides size measurements for gears based on measuring across a number of teeth (spanning these teeth). Rather than measuring across the entire gear, like with Measurement over Pins, span measurements use calipers to measure across a fixed number of gear teeth. As gears grow larger, the span measurement may be easier for an operator, and doesn't require giant calipers.

Input your gear parameters to find the acceptable range for the number of teeth to measure over, choose your number, then calculate the correct measurement to check out your gear. 
Results conform to ANSI/AGMA 2002-D19 published in December 2019

The default Manufacturing Profile Shift Coefficient is 0. Positive values result in thicker teeth, as if your cutting tool did not cut to a full depth, while negative values result in thinner teeth.

Gear Showing Pins for Measurement