This tool converts WGS-84 latitude and longitude to UTM — Universal Transverse Mercator — coordinates, the metre-based grid system used by topographic maps, militaries and GIS worldwide. It returns the zone number, the hemisphere, and the easting and northing in metres.
How it works
UTM divides the globe into 60 zones, each 6° of longitude wide. The zone number is:
zone = floor((longitude + 180) / 6) + 1Within a zone, the point is projected with a transverse Mercator projection on the WGS-84 ellipsoid, scaled by the central-meridian scale factor k0 = 0.9996. The math evaluates a Karney-style series in the conformal latitude, then adds a false easting of 500000 m so eastings are positive, and (in the southern hemisphere) a false northing of 10000000 m so northings are positive there too.
Worked example
Mount Everest sits at approximately 27.9881° N, 86.9250° E. Converting to UTM:
- Zone: 45N (N for northern hemisphere; zone computed as
floor((86.925 + 180) / 6) + 1 = 45) - Easting: roughly 492,653 m (metres east of the zone’s central meridian, offset by 500,000)
- Northing: roughly 3,096,185 m (metres north of the equator)
Note that the easting of 492,653 is slightly west of the 500,000 false-easting midpoint, meaning the point lies slightly west of zone 45’s central meridian (87° E).
Zone exceptions
Most zones are a simple 6° slice, but a few have political adjustments:
- Zone 32 is widened to 9° at latitudes 56–64° N to prevent Norway from being split.
- Zone 33 and 35 cover the Svalbard region with special shapes.
- The formula
floor((lng + 180) / 6) + 1applies everywhere else.
Reading the output
| Field | Meaning |
|---|---|
| Zone number | 1–60, identifying the 6° longitude band |
| Hemisphere | N or S (not a latitude band letter) |
| Easting | Metres east within the zone; 500,000 is the central meridian |
| Northing | Metres north; southern hemisphere adds 10,000,000 so it is never negative |
A point with easting below 500,000 is west of the zone’s central meridian; above 500,000 is east. Northings in the southern hemisphere are large numbers (for example 7,200,000 m) because of the 10,000,000 false northing.
When to use UTM vs other systems
UTM is the preferred choice when you need metric distances and calculations — it is essentially a flat Cartesian grid where you can subtract two eastings to get a distance in metres (within the same zone). For military-style compact references use MGRS, which encodes the same grid. For human-readable latitude/longitude labels, convert to DMS or decimal. Everything runs locally in your browser. To reverse the calculation, use the UTM to Lat/Lng converter.