Maidenhead Grid Square Lookup
Find, visualize, and compare Maidenhead locator grid squares used by ham radio operators worldwide.
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What is a Maidenhead grid square?
The Maidenhead Locator System (also known as the QRA Locator or IARU Locator) is a geographic coordinate system used by amateur radio operators to describe their location concisely. It was developed in 1980 by a group of VHF managers meeting in Maidenhead, England.
A 4-character grid square (e.g. DN70) covers an area of 2° latitude × 1° longitude — roughly 110 km × 111 km near the equator. A 6-character grid square (e.g. DN70lj) subdivides that into a 5′ × 2.5′ cell, narrowing the location to a few kilometers.
Grid squares are commonly exchanged in VHF/UHF contests, satellite operation, meteor scatter, and EME (Earth–Moon–Earth) contacts to identify stations and calculate distances and beam headings.