🗺️ Grid square & distance
Lat/lon ↔ Maidenhead grid, plus the distance and bearing between two grids.
Lat/lon → grid square
- 4-character
- EM26
- ≈ 70 × 100 mi field
- 6-character
- EM26ad
- ≈ 3 × 4 mi - what you say on the air
Grid → centre, and the path between two grids
- Distance
- 102.9 mi
- 165.6 km
- Bearing A → B
- 253° WSW
- true north, great circle
- Bearing B → A
- 73°
Grid squares are how hams give a location without an address: Tulsa is EM26, Oklahoma City EM15. ChatterBack stores members at 6-character precision by default. Distance uses the centres of the squares, so two 4-character grids can be off by up to ~50 miles.