MGRS ConverterLat/Long to MGRS & MGRS to Lat/Long (Military Grid Reference System)
MGRS gives a location as grid zone, 100 km square and easting/northing, for example 18S UJ 23478 06483 for the Washington Monument. Convert latitude and longitude to MGRS (4, 6, 8 or 10-digit) and back, get UTM and DMS at the same time, and use your phone’s GPS to find your own grid.
Uses the WGS 84 ellipsoid and the UTM/MGRS rules published by the National Geospatial-Intelligence Agency (NGA); validated against a reference geodesy library.
10-digit · 1 m
Inside the 100 km square
What is the Military Grid Reference System (MGRS)?
MGRS is the NATO standard for giving a location as a grid zone, a 100-kilometer square ID and an easting and northing, such as 18S UJ 23478 06483 for the Washington Monument. It is built on the UTM projection and the WGS 84 datum, works in meters instead of degrees, and lets you choose precision from 10 km down to 1 m by adding digits. U.S. forces, search and rescue, FEMA and many first responders use it because it is quick to read on a map and easy to say over the radio.
How to read an MGRS coordinate
| Part | Name | What it means |
|---|---|---|
| 18 | UTM zone | One of 60 north-south strips, each 6° of longitude wide |
| S | Latitude band | 8° bands lettered C to X (I and O are skipped) |
| UJ | 100,000 m square | Column letter (easting) and row letter (northing) of the 100 km square |
| 23478 | Easting | Meters east inside the square (read right) |
| 06483 | Northing | Meters north inside the square (read up) |
- Find the grid zone18S tells you the 6° zone (18) and 8° latitude band (S). On a map sheet it is printed in the margin.
- Find the 100 km squareUJ narrows it to one 100 × 100 km square inside that zone.
- Read right, then upSplit the digits in half. The first half is the easting (move right along the bottom), the second half the northing (move up). “Right and up” is the rule.
- Count the precisionFive digits each way is 1 m, four is 10 m, three is 100 m. An 8-digit grid (4 + 4) is good to 10 meters.
MGRS precision: 4, 6, 8 and 10-digit grids
| Grid reference | Precision (square size) | Typical use |
|---|---|---|
| 2 digits (e.g. 18S UJ 2 0) | 10 km | Area of operations, large region |
| 4 digits (UJ 23 06) | 1 km | Town, grid square on a 1:50,000 map |
| 6 digits (UJ 234 064) | 100 m | Building or field; common for land navigation |
| 8 digits (UJ 2347 0648) | 10 m | Vehicle, landing zone, call for fire |
| 10 digits (UJ 23478 06483) | 1 m | Survey-grade point; GPS output |
How the conversion works
Truncate, never round. MGRS references always describe the lower-left (south-west) corner of a square, so extra digits are dropped rather than rounded. Our converter follows that rule and also shows the center of the square when you convert back.
MGRS vs UTM vs latitude/longitude
Same projection as MGRS but written with full numbers (18N 323478 4306483). MGRS replaces the leading digits with the 100 km square letters, so it is shorter.
Angles on the globe (38.8895, −77.0353). Universal, but harder to measure distance with on a paper map.
Always easting first. Swapping the halves can put you kilometers off.
Old maps may use NAD27 or local datums; positions can shift by 100 m or more. This tool uses WGS 84, the same as GPS.
Related military calculators
Every pay, retirement, VA, PT test, ASVAB and time tool in one place, filtered by who you are.
Thinking about geospatial or land navigation jobs? Check which ones your ASVAB scores qualify for.
MGRS FAQ
Type the coordinates as decimal degrees or degrees-minutes-seconds and pick a precision. The converter projects them to UTM on the WGS 84 datum and builds the grid zone, 100 km square letters, easting and northing. 38.8895, −77.0353 becomes 18S UJ 23478 06483.
Switch to MGRS → Lat/Long and enter the grid with or without spaces. You get the center of the square and its south-west corner in decimal degrees and DMS, plus a map link.
An 8-digit grid has four easting and four northing digits, locating a 10 m square. It is the usual standard for calls for fire, landing zones and MEDEVAC requests.
Yes. Split the numbers in half. Read the first half to the right (easting) along the bottom of the map, then the second half up (northing). Soldiers remember it as “read right, then up.”
MGRS is built on UTM but replaces the leading digits of the easting and northing with two 100 km square letters, which makes references shorter and easier to say. Both use the same zones and meters.
Modern MGRS uses WGS 84, the same datum as GPS. Older maps on other datums (such as NAD27) can place the same grid reference a hundred meters or more away.
No. MGRS covers 80°S to 84°N. Polar regions use the Universal Polar Stereographic (UPS) grid.
They are skipped so they cannot be confused with the numbers 1 and 0 when written or spoken.
We tested it against a reference geodesy library on over 4,000 random points worldwide. All matched to within 1 meter, the smallest unit of a 10-digit grid.
Yes. Tap Use my location and allow location access. Your phone or browser provides the position, and the conversion happens on your device; nothing is sent to us.
People also search for:
Manzoor Ahmad
Calculator developer & web designer · 13+ years in web development and SEO
Last reviewed: October 30, 2026I am a pharmacist turned tech geek, and I design, code and test every calculator on DexoCalc myself. I have not served in the military, so this tool does not run on opinion: the conversion uses the published transverse Mercator equations on the WGS 84 ellipsoid, and before publishing I checked it against an independent reference library on 4,009 points worldwide, including the Norway and Svalbard zone exceptions.
Spot a result that does not match an official source? Tell me and I will re-check it.
Sources
- NGA: Office of Geomatics (UTM, MGRS, WGS 84)
- U.S. Army TC 3-25.26: Map Reading and Land Navigation
- USGS: The Universal Transverse Mercator (UTM) grid
- FGDC: U.S. National Grid standard
Disclaimer: DexoCalc is independent and not affiliated with the Department of Defense (Department of War), the Department of Veterans Affairs or any military branch. Results are educational estimates; official records and your chain of command decide.
Keep this tool one tap away
Add DexoCalc to your Google Preferred Sources or bookmark this page so it is there the next time you need it.