UTM Coordinate Converter
Convert latitude / longitude to UTM zone, easting and northing (and back).
Overview
The UTM Coordinate Converter translates between latitude/longitude and Universal Transverse Mercator coordinates. Enter a lat/lng and the tool returns the UTM zone, hemisphere, easting and northing in metres. Enter a UTM triplet and the tool returns the corresponding latitude and longitude on the WGS84 ellipsoid. It is the everyday workhorse for surveying, military mapping, geocaching and any task that prefers metric distances over angular coordinates.
UTM divides the world into 60 longitudinal zones, each 6 degrees wide, plus polar caps handled separately by UPS. Inside each zone, coordinates are given as a (false) easting in metres east of the zone's central meridian and a (false) northing in metres north of the equator (or, in the southern hemisphere, north of an offset reference). The result is a Cartesian grid in which distances and areas can be measured directly in metres - a huge convenience when you are walking off a property line or planning a drone flight.
How it works
UTM is a family of transverse Mercator projections, one per zone. The tool first determines the zone number from longitude (zone = floor((lng + 180) / 6) + 1) and the latitude band letter for the MGRS-style designator. It then projects the lat/lng to UTM easting and northing using the ellipsoidal Transverse Mercator equations on the WGS84 ellipsoid, with the standard 0.9996 scale factor and a false easting of 500,000 m. Southern hemisphere coordinates add a false northing of 10,000,000 m so the values stay positive.
Decoding inverts the projection using the standard Krüger-series inverse, again on WGS84. The tool handles all 60 zones plus the special widened zones (Norway's zone 32V and the Svalbard zones 31X-37X).
Examples
- (51.5074, -0.1278) - central London - converts to zone 30U, easting 699,319 m, northing 5,710,158 m.
- (40.7128, -74.0060) - New York City - converts to zone 18T, easting 583,960 m, northing 4,507,523 m.
- (-33.8688, 151.2093) - Sydney - converts to zone 56H, easting 334,873 m, northing 6,251,580 m.
- Zone 33N, easting 500,000, northing 0 decodes to (0, 15) - the central meridian of zone 33 on the equator.
FAQ
Why are there so many UTM zones?
Each zone is 6 degrees of longitude wide so that the Transverse Mercator projection's scale distortion stays under 1 part in 1000 across the zone. More zones would be more precise; fewer would be too distorted at the edges.
What are the special zones near Norway?
Zone 32V is widened to cover southwest Norway and zones 31X to 37X are restructured around Svalbard. Both adjustments date to original UTM design choices for those areas.
How do I write a UTM coordinate?
The standard form is zone hemisphere easting northing - for example 30U 699319 5710158. The latitude band letter (N, U, T...) is preferred over a bare N/S hemisphere when full MGRS-style precision is needed.
Is UTM the same as MGRS?
No. MGRS is built on top of UTM (and UPS at the poles) but packages the coordinates into an alphanumeric string with letter-based grid square identifiers. UTM is the underlying projected coordinate system.