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MGRS DD

Convert Military Grid Reference System to Decimal Degrees

To convert MGRS to DD: parse the grid zone designator, identify the 100km square from the two-letter identifier, compute absolute UTM easting and northing, then apply the inverse UTM projection.

MGRS to DD Converter

DD Decimal Degrees

DMS Deg. Min. Sec.

DDM Deg. Decimal Min.

UTM Univ. Trans. Mercator

MGRS Military Grid

Geohash Base32

Plus Code Open Location Code

How to Convert MGRS to DD: Step by Step

  1. 1 Parse the MGRS string into: Zone Number, Zone Letter, Column Letter, Row Letter, Easting digits, Northing digits.
  2. 2 Convert Column Letter to absolute easting using the column set for the zone.
  3. 3 Convert Row Letter to northing within a 2,000km cycle, then resolve the correct cycle using the zone letter.
  4. 4 Pad the numeric part to 5 digits each for 1m precision.
  5. 5 Apply the inverse UTM-to-latlong projection formula.

Worked Example

Input 31UDQ4825111943

Latitude conversion:

Zone 31U | DQ → Easting 448251, Northing 5411943 | Inverse UTM → 48.8584°N

Longitude conversion:

Inverse UTM → 2.2945°E

Result:

48.858400, 2.294500

Why Convert MGRS to DD?

MGRS is used on NATO military maps, US Army training materials, and defense contractor systems. Converting to DD is needed to use the location in civilian GPS apps or mapping software.

Common Mistakes to Avoid

  • Incorrect 100km square resolution due to wrong cycle
  • Confusing MGRS column and row letters
  • Not padding the numeric portion to 5 digits each