How to use the initial compass bearing calculator
Find the starting compass bearing from one point on Earth to another. Enter latitude of point 1, longitude of point 1, latitude of point 2, longitude of point 2 in the fields above; the initial bearing from north is computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “compass bearing between two points”, “initial bearing great circle”, “direction from A to B”, “calculate initial compass bearing”, “find initial bearing from north”.
Formula
Variables
- lat1 — Latitude of point 1 (°)
- lon1 — Longitude of point 1 (°)
- lat2 — Latitude of point 2 (°)
- lon2 — Longitude of point 2 (°)
Worked example
With latitude of point 1 = 51.5074 °, longitude of point 1 = -0.1278 °, latitude of point 2 = 48.8566 °, longitude of point 2 = 2.3522 °, the calculator gives initial bearing from north ≈ 148.1156 °.
Frequently asked questions
What is the initial compass bearing calculator used for?
Find the starting compass bearing from one point on Earth to another. It helps with questions such as “compass bearing between two points”, “initial bearing great circle”, “direction from A to B”.
What is the formula for the initial compass bearing calculation?
Initial bearing from north (°) = (atan2d(sin(lon2-lon1) × cos(lat2),cos(lat1) × sin(lat2)-sin(lat1) × cos(lat2) × cos(lon2-lon1))+360)%360. Here lat1 is latitude of point 1 (°), lon1 is longitude of point 1 (°), lat2 is latitude of point 2 (°), lon2 is longitude of point 2 (°).
What inputs do I need for the initial compass bearing calculator?
You need latitude of point 1 in °, longitude of point 1 in °, latitude of point 2 in °, longitude of point 2 in °. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the initial compass bearing calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the initial compass bearing result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.