Great-Circle Navigation Calculator

Solve great-circle navigation on a sphere: the initial and final compass bearing between two latitude/longitude points, the great-circle distance, the midpoint, and — in reverse — the destination point reached from a start, a bearing and a distance. Two modes: point-to-point (enter start and end) or destination (enter start, bearing and distance). All on a spherical Earth (mean radius 6371 km); accurate enough for everyday navigation, less precise than ellipsoidal methods for very long routes. Pure trigonometry, in your browser.