Your Maidenhead locator from GPS or coordinates, and distance & bearing between any two grids.
or enter coordinates
West longitude and south latitude are negative.
Your grid square
Not a valid grid square
Not a valid grid square
A Maidenhead grid square encodes location in pairs: field (FN), square (FN20, ~70 × 100 mi), subsquare (FN20xa, ~3 × 4 mi). Most exchanges use 4 or 6 characters.
Distance uses the great-circle path; bearing is the initial heading from the "from" grid — point your beam there.
Distances between grids are measured center-to-center, so 4-character grids can be off by up to ~50 miles. Use 6 characters when it matters.
CQ zones (1–40) are the Worked All Zones regions used in CQ contests; ITU zones (1–90) are used in IARU HF Championship exchanges; the ITU region (1–3) determines your band plan.
Zone lookups here are geometric approximations — real zone edges follow political borders in places, so if you're near a boundary (or at sea), double-check against the official WAZ/ITU maps.
Your GPS position is processed entirely in your browser — nothing is sent to the server.