The compass bearing from one point to another: initial, final, and rhumb line.
How this tool works
On a sphere, the direction to a destination changes as you travel along the shortest path, so the tool gives three numbers. The initial bearing is the compass direction you set off on along the great circle; the final bearing is the direction you arrive on; and the rhumb-line bearing is the single constant compass course that also gets you there, along a slightly longer path. All bearings are measured clockwise from true north, not magnetic north.
What you can do with it
- Find the compass direction from any point to any other
- See how much the great-circle bearing changes over long routes
- Get the constant rhumb-line course used in traditional navigation
- Convert bearings to 16-point compass names automatically
Why use it
What direction is Tokyo from Seattle has a genuinely surprising answer (northwest, not west), and the difference between initial, final, and rhumb bearings is exactly what makes long-distance navigation interesting. This tool shows all three so the difference is visible.