About This Tool
The Coordinate Converter is a free online tool that converts a single position between six coordinate formats: decimal degrees (DD), degrees minutes seconds (DMS), degrees decimal minutes (DDM), UTM, MGRS, and GARS. Enter a coordinate in any one format and get it back in all the others, with a map pin so you can verify the spot. All math runs on the WGS84 datum — the same reference GPS receivers and mainstream mapping apps use — and the conversion happens entirely in your browser, with no account and nothing sent to a server.
The conversion engine is the same one used in the MyGPSConverter iOS app: Snyder's forward UTM projection, the Karney (2011) inverse, NGA-style MGRS grid squares, and the NGA GARS algorithm.
How to Convert Coordinates
- Pick your input format from the format cards, or click one of the example inputs above to load it.
- Type the coordinate into the structured fields, or paste a full coordinate string — the fields auto-fill from a paste.
- Optionally use the current-location button to fill the fields from your device's GPS (your browser will ask permission).
- Click Convert to see the position in every format, plotted on the map.
- Copy any single result with its Copy button, or use Copy Report for a plaintext summary of all formats with map links.
Supported Coordinate Formats
| Format | Example | Notes |
|---|---|---|
| Decimal Degrees (DD) | 32.312064, -114.539201 | The native format of most apps and web maps |
| Degrees Minutes Seconds (DMS) | 32° 18' 43.43" N, 114° 32' 21.12" W | Traditional paper-map and aviation style |
| Degrees Decimal Minutes (DDM) | 32° 18.724' N, 114° 32.352' W | Common on marine GPS units and geocaching |
| UTM | 11S 731676mE 3577687mN | Zone plus metric easting/northing; standard 6° zones, valid 80°S–84°N |
| MGRS | 11SQR3167577686 | Military grid reference down to 1-meter precision |
| GARS | 131LE29 | Area reference in 5'×5' cells; input converts to the cell center |
Convert UTM to Latitude/Longitude (and Back)
The most common conversion is between UTM and latitude/longitude. To go from UTM to lat/long, enter the zone, easting, and northing (for example 11S 731676mE 3577687mN) and the converter returns the position as decimal degrees, DMS, and DDM at once. To go the other way, enter latitude and longitude in any style — 32.312064, -114.539201 works, and so does a pasted DMS string — and read the UTM result off the output panel.
Two things to watch when converting UTM: the zone letter matters (a northing in band S is a very different place than the same northing in band C), and UTM eastings/northings are in meters, so a one-digit typo moves the point by a power of ten. The map pin under the results is the quickest sanity check — if the pin isn't where you expected, check the zone first.
Frequently Asked Questions
Which datum does the converter use?
WGS84 only — the datum used by GPS and virtually all modern apps. Coordinates read off older maps (for example NAD27 topos) need a datum shift first or they can be off by up to a couple hundred meters.
Are my coordinates sent to a server?
No. All parsing and conversion math runs locally in your browser; the only network requests are the map tiles used to display the pin.
Does it work in polar regions?
UTM and MGRS conversions cover 80°S to 84°N with standard zone rules; UPS polar zones and the Norway/Svalbard zone-width exceptions are not implemented.
Why does a GARS conversion look less precise?
GARS is an area reference system, not a point system — a cell identifies a 5-minute by 5-minute box, so converting from GARS returns the center of that cell.
Can it fill in my current position?
Yes. On devices with GPS or location services, the current-location button fills the input fields after you grant the browser permission.
Learn More
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