Enter values below to calculate the diameter of a bolt circle.
To measure the center distance between two holes of equal
diameter with an electronic caliper.
1. Use the inside jaws to measure the diameter of one of the holes. Before you
remove the caliper from the hole, press the button to zero the caliper while
it is set to the diameter of the hole.
2. Still using the inside jaws, measure the distance between the far surfaces of
the two holes. The caliper reading is the distance between centers of the