Lat Long to UTM Converter Calculator

Latitude (decimal degrees): North-south position on Earth. North is positive and south is negative.

Longitude (decimal degrees): East-west position on Earth. East is positive and west is negative.

Datum: The Earth model used by the coordinates. A datum mismatch can shift UTM values even when the same place is used.

UTM zone number: One of 60 longitude zones, normally 6 degrees wide, with Norway and Svalbard exceptions [1].

Latitude band: A letter used in UTM grid labeling to show the latitude band. It is helpful for labeling, but software often still asks for hemisphere separately.

Hemisphere: Whether the point is in the Northern or Southern Hemisphere.

Easting: The east-west UTM value in meters, measured within the chosen zone from a false origin.

Northing: The north-south UTM value in meters. In the Southern Hemisphere, a false northing keeps the number positive.

Matching EPSG code: A standard GIS code for the projected coordinate system, such as WGS 84 / UTM zone 18N = EPSG:32618 [3] or NAD83 / UTM zone 18N = EPSG:26918 [2].

Zone center longitude: The central meridian of the UTM zone, which helps explain why nearby points can switch zones near a boundary.

Mistake: Entering west longitude as a positive number in Longitude (decimal degrees) .
Fix: Use a negative value for west longitudes, such as -74.0060 for New York City.

Mistake: Entering south latitude as a positive number in Latitude (decimal degrees) .
Fix: Use a negative value for places south of the equator so the Hemisphere and Northing come out correctly.

Mistake: Picking the wrong Datum and then wondering why the Easting and Northing do not match another map layer.
Fix: Match Datum to the source data first, then verify the Matching EPSG code before exporting or comparing coordinates.

Mistake: Copying only Easting and Northing without the UTM zone number or Hemisphere .
Fix: Copy the full UTM coordinate or include Easting , Northing , UTM zone number , Hemisphere , and Datum together.

Mistake: Treating Latitude band as the same thing as Hemisphere in GIS software.
Fix: Use Hemisphere when software asks for north or south, and treat Latitude band as an extra grid label only.

Mistake: Using a point above 84 degrees north or below 80 degrees south and expecting a normal UTM coordinate .
Fix: Stay within the standard UTM range for this tool; outside that range, use a polar system instead.

• This calculator uses standard UTM only for latitudes from 80 degrees south to 84 degrees north. Outside that range, it should not be used.
• It converts latitude and longitude to UTM on the selected datum, but it does not perform a separate datum transformation between coordinate reference systems.
• NAD83 EPSG codes are supplied only for northern UTM zones 1 through 23. Confirm the code area of use in your GIS: the ellipsoid projection alone does not validate a datum at any arbitrary location.
• Zone selection follows the automatic UTM rule, including southwest Norway and Svalbard exceptions. Very close to a zone boundary, nearby datasets may use the neighboring zone even though this converter gives the mathematically correct zone for the input longitude.
• Displayed rounding affects only how Easting and Northing are shown, not the underlying calculation.
• Results are only as good as the input coordinates. If the original latitude and longitude were rounded or recorded in a different datum, the UTM output will differ too.

What the calculator does

This converter takes Latitude (decimal degrees) and Longitude (decimal degrees), picks the standard UTM zone from longitude, then applies the forward ellipsoidal Transverse Mercator projection on the selected datum. It then adds the standard UTM false easting and, in the Southern Hemisphere, the standard false northing.

NGA UTM coordinate-system guidance, including Norway and Svalbard exceptions.

Core steps

zone = floor((longitude + 180) / 6) + 1

The zone is clamped to 1 through 60 so exactly 180 degrees stays in zone 60. Between 56 and 64 degrees north, longitudes 3 to 12 degrees east use zone 32. Between 72 and 84 degrees north, Svalbard zones are 31 for 0–9 degrees east, 33 for 9–21, 35 for 21–33 and 37 for 33–42 (upper longitude bounds excluded).

zone center longitude = zone * 6 - 183

This gives the central meridian for the chosen UTM zone. UTM divides the world into 60 zones that are 6 degrees wide [1].

k0 = 0.9996

false easting = 500000 m

false northing south = 10000000 m

These are the standard UTM projection constants.

Datum and ellipsoid

For Datum = WGS 84, the calculator uses semi-major axis 6378137.0 m and inverse flattening 298.257223563. For Datum = NAD83, it uses the GRS 1980 ellipsoid with semi-major axis 6378137.0 m and inverse flattening 298.257222101.

f = 1 / inv_f

e2 = f * (2 - f)

The flattening value f gives the ellipsoid eccentricity squared e2, which is needed for the projection series.

Projection math

The calculator converts latitude, longitude, and the central meridian to radians, then uses the standard ellipsoidal forward Transverse Mercator series. In compact form, it computes the meridional arc and series terms usually named M, N, T, C, and A.

x = k0 * N * (A + (1 - T + C) * A^3 / 6 + (5 - 18T + T^2 + 72C - 58e'^2) * A^5 / 120)

y = k0 * (M + N * tan(phi) * (A^2 / 2 + (5 - T + 9C + 4C^2) * A^4 / 24 + (61 - 58T + T^2 + 600C - 330e'^2) * A^6 / 720))

Easting = 500000 + x

Northing = y + 10000000 for the Southern Hemisphere, otherwise y

This is an ellipsoidal method, not a simple spherical shortcut, so it matches the kind of workflow GIS users expect.

EPSG code mapping

WGS84 north: EPSG = 32600 + zone

WGS84 south: EPSG = 32700 + zone

NAD83 north, zones 1 through 23 only: EPSG = 26900 + zone

For example, zone 18 north on WGS 84 maps to EPSG:32618 [3], while zone 18 north on NAD83 maps to EPSG:26918 [2].

Mini example

If you enter latitude 40.7128 and longitude -74.0060 with Datum = WGS 84, the zone calculation gives zone 18. The zone center longitude becomes -75 degrees. Because the latitude is positive, the hemisphere is North, so the matching EPSG pattern gives 32618. The calculator then runs the forward projection to get Easting and Northing in meters and combines them into the full UTM coordinate.

Notes on interpretation

If the point is very close to a zone edge, the calculator keeps the mathematically correct zone for that longitude and adds a note because nearby data may be stored in the next zone. The Latitude band is included for labeling help, but GIS software that asks for hemisphere should use Hemisphere, not the band letter alone.

Assumptions used here

This tool assumes standard UTM coverage only, blocks latitude values outside 80 degrees south to 84 degrees north, rejects longitude outside -180 to 180 degrees, and does not invent a southern NAD83 EPSG code. Display rounding is applied only after the main calculation is finished.