Great Circle Calculator

Compute true course and distance between points.

Enter lat/lon of points, select distance units and earth model and click "compute". Lat/lons may be entered in DD.DD, DD:MM.MM or DD:MM:SS.SS formats.

Note: If either point is close to a pole, the course may be inaccurate.

Distance Units: nmkmsmft Earth model: Spherical (1'=1nm) WGS84/NAD83/GRS80 Clarke (1866)/NAD27 International Krasovsky Bessel (1841) WGS72 WGS66 FAI sphere User defined

Compute lat/lon given radial and distance from a known point

Enter lat/lon of initial point, true course and distance. Select distance units and earth model and click "compute". Lat/lons may be entered in DD.DD, DD:MM.MM or DD:MM:SS.SS formats.

Note: The starting point cannot be a pole.

Distance Units: nm km sm ft Earth model: Spherical (1'=1nm) WGS84/NAD83/GRS80 Clarke (1866)/NAD27 International Krasovsky Bessel (1841) WGS72 WGS66 FAI sphere User defined