Lat-Long to UTM Converter
Universal Transverse Mercator (UTM) expresses position as a zone number plus an easting and northing in meters, which is convenient for distance and area work because the units are metric and locally Cartesian. This converter takes WGS84 latitude and longitude in decimal degrees, picks the correct 6-degree zone, and applies the standard transverse Mercator forward projection (the USGS Snyder series with scale factor 0.9996) to return the zone, hemisphere, easting and northing. Use north positive for latitude and east positive for longitude.
UTM projection basis
Zone = floor((longitude + 180) / 6) + 1
Central meridian = zone * 6 - 183 degrees
Ellipsoid: WGS84 a = 6,378,137 m, 1/f = 298.257223563
Scale factor k0 = 0.9996
False easting 500,000 m; false northing 10,000,000 m (south)
The easting and northing follow the standard transverse Mercator forward series (USGS Snyder). The series is truncated to the fourth-order terms used in operational UTM software.
UTM context
- UTM covers latitudes from 80 degrees south to 84 degrees north in 60 zones of 6 degrees each.
- Eastings are referenced to a false origin of 500,000 m at the central meridian.
- Southern hemisphere northings use a false 10,000,000 m origin to stay positive.
- WGS84 is the GPS datum; results differ slightly from NAD83 at the centimeter level.
- The Norway and Svalbard zone-width exceptions are not applied by this converter.
Lat-long to UTM: frequently asked questions
What is the UTM coordinate system?
Universal Transverse Mercator divides the Earth into 60 longitudinal zones, each 6 degrees wide, and projects each zone with a transverse Mercator projection. Positions are given as a zone number, an easting (meters east of the zone's false origin) and a northing (meters north of the equator, or from a false 10,000,000 m origin in the southern hemisphere).
Which ellipsoid does this converter use?
It uses the WGS84 ellipsoid, the standard datum for GPS, with a semi-major axis of 6,378,137 m and flattening of 1/298.257223563. The scale factor on the central meridian is 0.9996, the defined UTM value.
How is the UTM zone determined?
The zone number is floor((longitude + 180) / 6) + 1, giving zones 1 to 60. Each zone is 6 degrees wide and has a central meridian at zone times 6 minus 183 degrees. The Norway and Svalbard exceptions are not applied here.
What are false easting and false northing?
To keep coordinates positive, UTM adds a false easting of 500,000 m to every easting. In the southern hemisphere a false northing of 10,000,000 m is added so northings stay positive south of the equator. This converter applies both automatically.
How accurate is this conversion?
It uses the standard truncated series form of the transverse Mercator forward projection (the USGS Snyder formulation), accurate to a few millimeters within the normal UTM zone width. It is suitable for mapping and GIS use.
Official sources
- U.S. Geological Survey: U.S. Geological Survey.
- NOAA National Geodetic Survey: National Geodetic Survey.
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. See our methodology.