Coordinate converter
Paste a point in any common format, such as 40.7128, -74.0060, 40°42′46″N 74°0′22″W or a UTM reference like 18T 583959 4507351, and get the same place in every other format, plus a geo link you can paste into map apps.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Type or paste one point: latitude first, then longitude.
- Any common format works: decimal degrees (40.7128, -74.006), degrees–minutes–seconds with or without symbols (40 42 46 N, 74 0 22 W), degrees and decimal minutes, or UTM (18T 583959 4507351).
- Read the point in every other format. The copy buttons and the geo link make it easy to paste into a GPS app or a spreadsheet.
How the conversion works
Decimal degrees ↔ DMS. Degrees = whole part; minutes = fraction × 60; seconds = what is left × 60. Seconds are shown to one decimal (about 3 m), decimal minutes to three decimals (about 2 m).
Degrees ↔ UTM. The point is projected with the transverse Mercator series from Snyder’s Map Projections – A Working Manual on the WGS84 ellipsoid (a = 6,378,137 m, f = 1/298.257223563), with the scale factor 0.9996 on the central meridian. The zone is ⌊(longitude + 180) ÷ 6⌋ + 1, with the Norway and Svalbard exceptions; the inverse uses the footpoint latitude series of the same book.
Worked example
40.7128, -74.0060 (Lower Manhattan) gives:
- DMS: 40°42′46.1″ N, 74°00′21.6″ W
- Decimal minutes: 40°42.768′ N, 74°00.360′ W
- UTM: 18T 583959 4507351 – zone 18 (78° W to 72° W), band T (40° N to 48° N), 583,959.4 m east and 4,507,351 m north.
Typing 18T 583959 4507351 back returns 40.7128, -74.006.
Common mistakes
- Swapping the order: almost every format writes latitude first. 74, 40 is a point in the Arctic Ocean, not New York.
- Forgetting the sign: 74.006 without W or a minus is east of Greenwich.
- Reading the UTM band N as “north”: N is just the band from 0° to 8° N; bands C to M are south of the equator.
- Mixing datums: a point read from an old local-datum map needs a datum shift before it matches GPS.
Frequently asked questions
How do I convert degrees, minutes and seconds to decimal degrees?
Divide the minutes by 60 and the seconds by 3600 and add them to the degrees: 40°42′46″ = 40 + 42/60 + 46/3600 = 40.7128°. South latitudes and west longitudes are negative, so 74°0′22″ W is −74.0061°.
What is UTM and why does it have a zone and a letter?
UTM splits the Earth into 60 zones, each 6° of longitude wide, and gives a point as metres east (easting) and north (northing) inside its zone. The letter is the 8° latitude band. Each zone's central meridian has an easting of 500,000 m; in the southern hemisphere 10,000,000 m is added to the northing so it stays positive.
Which datum does the converter use?
WGS84, the datum of GPS and of most web maps. Old paper maps may use a local datum (for example NAD27 or Pulkovo 1942); coordinates on those can differ from WGS84 by tens to hundreds of metres, and this tool does not shift between datums.
Why is my UTM a metre different from another tool?
The result is rounded to whole metres, and tools differ in the series they use for the projection. The formulas here (Snyder's, used by the USGS) agree with the round trip to about a centimetre inside a zone.
Does it handle Norway and Svalbard?
Yes. Zone 32V is widened over south-western Norway, and between 72° and 84° N only zones 31X, 33X, 35X and 37X are used, as the UTM grid defines. The converter picks those zones automatically.