An Inverse calculation is used to find the distance and direction between two points.
For example, a user may need to know the distance between Point A and Point B (assuming that the coordinates of each point were known).
The user would enter the coordinates of each point. The calculator will calculate the forward (A to B) azimuth/distance and the back azimuth/distance (B to A). Geodetic or Grid calculations may be specified.
Note:
Geodetic forward and back azimuths may not have a difference of 180 degrees unless the points lie on the Equator or a meridian (i.e. a great circle).