To convert an MGRS grid reference to latitude and longitude, paste it in, with or without spaces. The converter returns the decimal degrees of the south-west corner of the grid square, the square's centre and its size, on the WGS84 datum. It handles references from 1 m to 10 km precision and whole lists. Nothing leaves your browser.
- Free, no signup
- Spaced or compact references
- Corner and centre of the square
- Runs in your browser
Convert many at once
One reference per line, with or without spaces, for example 18T WL 80735 04706 or 18TWL8073504706. References of different precision can be mixed.
How to convert MGRS to latitude and longitude
- Enter the MGRS reference. Include the grid zone (such as
18T), the two 100 km square letters and an even number of digits. Spaces are optional. - Click Convert. The latitude and longitude of the square's south-west corner appear, with the cell size and the cell centre.
- Check the cell size. A reference with fewer digits names a larger square. At 1 m precision the corner and the centre differ by less than a metre.
- Or convert a list. Paste many, one per line, and download the results as a CSV.
What the result means
An MGRS reference names a square, not a single point. The square is 1 m on a side with five digits each, 10 m with four, 100 m with three, 1 km with two and 10 km with one. This converter returns two positions:
- The south-west corner. This is the numeric position the reference starts at, and is what most MGRS libraries return.
- The centre of the square. This is often the better choice when the reference is short, for example when mapping a 1 km square.
At full 1 m precision the two differ by about 0.7 m, which rarely matters.
Worked example
Convert 18T WL 80735 04706. The grid zone 18T is UTM zone 18, latitude band T. The square letters WL, together with the zone, place the 100 km square, and the digits give 80735 m east and 04706 m north inside it. That is UTM easting 580735 m and northing 4504706 m, which converts on WGS84 to:
latitude = 40.689298 longitude = -74.044509 (south-west corner of the 1 m square)
This is the Statue of Liberty in New York harbour.
Formats this converter understands
| You type | Read as |
|---|---|
18T WL 80735 04706 | 1 m square, spaced |
18TWL8073504706 | Same, compact |
18tWL 8073 0470 | 10 m square; lower case is accepted |
43R EK 78 76 | 1 km square |
43R EK | The whole 100 km square |
The digits must be an even count, with the same number for easting and northing. Row and column letters must be valid for the zone; a reference that cannot exist is rejected with the reason.
Common mistakes
- Odd number of digits.
18TWL807350470has 9 digits, so the easting and northing cannot be split. Check for a dropped digit. - Wrong or missing band. The band letter (T in
18T) removes the 2,000 km ambiguity in the row letters. A wrong band can place the point in a different part of the world, and the page rejects a reference whose band and position disagree. - Letters I and O. They are not used in MGRS to avoid confusion with 1 and 0. A reference containing them is rejected.
- Using the wrong datum. This page reads references as WGS84. A reference taken from an older NAD27 map points to a slightly different place.
What this converter does and does not do
- WGS84 only. It uses the modern MGRS letter scheme on the WGS84 ellipsoid. The older Bessel-ellipsoid lettering is not supported.
- 80° S to 84° N. Polar UPS references are not supported.
- Accuracy. The conversion matches the open-source
mgrslibrary and PROJ; we tested hundreds of points worldwide, and a round trip returns to within the 1 m grid square. - Runs in your browser. No coordinates are sent to a server.
Related converters
To go the other way, use lat long to MGRS. For the UTM values behind a reference see UTM to lat long, and to plot the result use CSV to KML.
Frequently asked questions
How do I convert an MGRS reference to latitude and longitude?
Enter the reference, for example 18T WL 80735 04706, and click Convert. The page returns the latitude and longitude of the square's south-west corner and its centre in decimal degrees.
Does MGRS name a point or a square?
A square. With five digits each it is 1 m wide, with fewer digits it is larger. The result gives the south-west corner and the centre.
Which corner does the result use?
The south-west corner, which is what most MGRS software returns. The centre is shown separately.
Do I need the spaces in the reference?
No. 18TWL8073504706 and 18T WL 80735 04706 are the same reference.
Why was my reference rejected?
Common reasons are an odd number of digits, the letters I or O, a column or row letter that does not exist in that zone, or a band that disagrees with the position. The error says which.
What do the first three characters mean?
The number and letter, such as 18T, are the UTM zone and latitude band. The next two letters are the column and row of the 100 km square.
What is the difference between MGRS and UTM?
MGRS writes the same grid with two letters in place of the leading digits of the easting and northing. The page also shows the UTM easting and northing.
Which datum does it use?
WGS84. If the reference was made on an older datum such as NAD27, it will point to a position some metres to hundreds of metres away.
Does it support polar MGRS?
No. The polar UPS grid beyond 80° S and 84° N is not covered.
Can I convert a list at once?
Yes. Paste one entry per line into the batch box, click Convert list, then copy the results or download them as a CSV. Lines that cannot be read are flagged with the reason instead of being skipped silently.
Does it send my coordinates to a server?
No. The conversion runs in your browser, and once the page has loaded it needs no connection.
Related tools and guides
Need survey data cleaned, projected or mapped at scale? Sagarmekhla GIS Consultancy offers GIS and remote sensing services.
Request a consultationLast updated 2026-10-15. Published by Sagarmekhla GIS Consultancy.