Glossary
MGRS
The Military Grid Reference System (MGRS) is the NATO standard way of writing a location as a grid zone, a 100 km square and a string of digits.
Context
In 38SND1234567890, 38S is the grid zone, ND is the 100 km square, and the ten digits are five of easting followed by five of northing. The digits always come in equal halves, and more digits mean a finer position: ten digits locate a point to 1 m, eight to 10 m.
How Gridnorth handles it
A grid reference read out digit by digit is one of the commonest sources of error in our tests. Gridnorth checks the format and puts an invalid one, such as an odd number of digits, in front of the operator before release. See the 9-line MEDEVAC walk-through.
Last reviewed September 29, 2026