Calculate the Radius of an Arc

Enter the width and height, then press "calculate" to get the radius. It works for arcs that are up to a semicircle, so the height you enter must be less than half the width.

Height (H):
Width (W):

To draw the arc:

Note: * The radius can become quite long and a compass no longer would work. In this case, just use a piece of string to swing the arcs.