MGRS Converter: Lat/Long to MGRS, UTM & USNG
Convert lat/long to MGRS, USNG and UTM or back, one point or a whole CSV at once. Reads DMS, DDM and UTM lines like 18T 585628 4511322. Runs in your browser.
Decimal degrees, degrees and decimal minutes, or degrees, minutes and seconds. Use N, S, E, W or a minus sign for south and west. Works from 80°S to 84°N; the polar UPS grid is not supported.
Spaces are optional. After the two square letters, give 2 to 10 digits: half easting, half northing.
Zone and band (18T) or hemisphere (18N, 18 south), then easting and northing in metres. Or fill in the parts:
- MGRS
- USNG
- UTM
- Decimal degrees
- Degrees, minutes, seconds
- Degrees, decimal minutes
- Grid zone
| Row | Input | Latitude, longitude | MGRS | UTM | Note |
|---|
How to use the MGRS converter
Choose what you are converting from and type or paste the coordinates. The result updates as you type and shows the point as MGRS, USNG, UTM, decimal degrees, degrees-minutes-seconds (DMS) and degrees with decimal minutes (DDM), each with a copy button. Use my location asks your browser for your position, and the precision menu sets the number of MGRS digits.
| Input | Example |
|---|---|
| Decimal degrees | 40.74844, -73.98566 |
| Degrees and decimal minutes | N40 44.906 W073 59.140 |
| Degrees, minutes, seconds | 40°44'54.4"N 73°59'08.4"W |
| MGRS or USNG | 18T WL 85631 11326 or 18TWL8563111326 |
| UTM | 18T 585631 4511327 or 18N 585631 4511327 |
Latitude comes first unless you label the values with N, S, E or W; south and west can also be written with a minus sign.
Band letter or hemisphere?
A UTM coordinate may give a latitude band after the zone (18T) or a
hemisphere (18N, 18S). N means north either way. S is ambiguous: band S
covers 32°N to 40°N, but S also stands for south. The converter reads S as
band S when the northing fits that band, about 3,540,000 to 4,432,000 m, and
as the southern hemisphere otherwise, and it says which it chose. To be
certain, write 18 south or pick the hemisphere in the menu.
Converting many points
In Batch mode, paste one coordinate per line in any of the formats above, or open a CSV file with a header row. Columns named like lat and lon, mgrs, utm, or zone, easting and northing are read, and the other columns are kept. Download CSV adds latitude, longitude, MGRS, UTM zone, band, hemisphere, easting and northing to each row, and an error column explains any row that could not be read.
How an MGRS grid reference is built
In 18T WL 85631 11326, 18T is the grid zone: UTM zone 18 and latitude
band T. Bands are 8° tall and lettered C (80°S) to X (72°N to 84°N, 12°
tall), skipping I and O. WL names a 100 km square, and 85631 11326
are the easting and northing inside it.
| Digits | Precision |
|---|---|
| 10 | 1 m |
| 8 | 10 m |
| 6 | 100 m |
| 4 | 1 km |
The digits are truncated, not rounded, so the last digit can be one lower than the rounded UTM value, and converting a reference back gives the centre of its square. USNG, the US National Grid, uses the same zones, letters and digits, written with spaces; its datum, NAD 83, is within about 2 m of WGS 84 in the United States.
UTM zones and their exceptions
UTM splits the world into 60 zones, each 6° of longitude wide and projected with transverse Mercator: scale factor 0.9996, false easting 500,000 m and, south of the equator, false northing 10,000,000 m. Zone 32V is widened to run from 3°E to 12°E around Norway, and around Svalbard zones 31X, 33X, 35X and 37X are widened while 32X, 34X and 36X are not used. The converter applies both.
Accuracy and limits
The math uses the WGS 84 ellipsoid and Krüger’s series, the method of GeographicLib and PROJ, and agrees with PROJ to well under a millimetre. MGRS and UTM cover 80°S to 84°N; the polar UPS grid (bands A, B, Y and Z) is not supported. Coordinates from old paper maps may use another datum, such as NAD 27 or ED 50, which can put the same point tens to hundreds of metres away.
Frequently asked questions
Is my location sent anywhere?
No. All conversions, including batch files, run in your browser. “Use my location” asks your browser for your position, and it stays on your device; nothing is uploaded or stored.
What is the difference between MGRS, USNG and UTM?
They are the same grid. UTM gives a zone number and two large numbers in metres. MGRS and USNG add a latitude band letter and replace the leading digits with two letters for the 100 km square, which makes references shorter and harder to misread.
Why do my last digits differ from another app?
MGRS digits are truncated to the square the point lies in, while UTM values are usually rounded, so they can differ by one in the last place. Apps that round MGRS, or use a datum other than WGS 84, can also give slightly different digits.
Does 18S mean band S or the southern hemisphere?
It depends on the writer. This converter reads S as band S (32°N to 40°N) when the northing fits that band and as the southern hemisphere otherwise, and tells you which it used. Write 18 south, or a band letter such as 18H, to avoid any doubt.
Can I convert coordinates near the North or South Pole?
Not here. North of 84°N and south of 80°S, MGRS uses the Universal Polar Stereographic grid, which this converter does not handle. It tells you when a point falls in that area.