Coordinate converter: decimal degrees, DMS and UTM
Type a coordinate or click the map
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The three formats below update together.
WGS 84 · geodesic · Guide, examples and sources below
What is the difference between decimal degrees, DMS and UTM?
Type a coordinate in any of the three formats and the other two update at once, with the point shown on the map. Click the map to read the coordinates of any spot.
All of them name the same place on the WGS 84 datum. Decimal degrees (DD) write latitude and longitude as plain numbers, with a minus sign for south and west. Degrees-minutes-seconds (DMS) split each number into 60ths, the way sailors and printed maps do. Degrees and decimal minutes (DDM) stop at minutes with a decimal. UTM gives a zone, an easting and a northing in meters on a flat grid, which is handy for distances on the ground.
| Format | Value |
|---|---|
| Decimal degrees | 43.642567, -79.387139 |
| Degrees-minutes-seconds | 43°38′33.24″ N, 79°23′13.70″ W |
| Degrees and decimal minutes | 43° 38.5540′ N, 79° 23.2283′ W |
| UTM (WGS 84) | 17N 630084 4833439 |
The CN Tower’s published UTM position is 17N 630084 4833438 (Wikipedia, UTM article). The converter reproduces it from the degrees-minutes-seconds position to the meter.
How do I convert decimal degrees to degrees, minutes and seconds?
Keep the whole degrees. Multiply the decimal part by 60: the whole number you get is the minutes. Multiply the new decimal part by 60 again: that is the seconds. The sign becomes a letter: positive latitude is N, negative is S, positive longitude is E, negative is W.
Worked example. 40.7128°: the whole degrees are 40. 0.7128 × 60 = 42.768, so the minutes are 42. 0.768 × 60 = 46.08 seconds. The result is 40° 42′ 46.08″. Going back, 42 ÷ 60 + 46.08 ÷ 3600 = 0.7128.
When rounding the seconds gives 60.00, the tool carries it to the next minute (and a minute that reaches 60 to the next degree), so you never see “59′ 60″”.
How does UTM work, and where does it not?
UTM splits the world between 80°S and 84°N into 60 zones, each 6° of longitude wide, numbered from 180°W. Inside a zone the map is a transverse Mercator projection with a scale factor of 0.9996 on the central meridian. The easting starts at 500,000 m on that meridian so it is never negative; in the southern hemisphere the northing starts at 10,000,000 m at the equator for the same reason. That is why a UTM coordinate needs the zone and the hemisphere (written as 17N or 56S) to be unambiguous.
Two exceptions are built in: zone 32 is widened to cover part of the Norwegian coast, and Svalbard uses zones 31, 33, 35 and 37 only. Beyond 84°N and 80°S the polar UPS grid is used instead, which this tool does not convert; it tells you so rather than returning a wrong number. The conversion uses Karney’s Krüger series to sixth order, a method with errors under 5 nanometers within 3,900 km of the central meridian.
How many decimals do I need?
| Decimals | Example latitude | Smallest step on the ground |
|---|---|---|
| 0 (whole degrees) | 45° | 111.14 km |
| 1 | 45.0° | 11.11 km |
| 2 | 45.00° | 1.11 km |
| 3 | 45.000° | 111.13 m |
| 4 | 45.0000° | 11.11 m |
| 5 | 45.00000° | 1.11 m |
| 6 | 45.000000° | 11.11 cm |
Six decimals of a degree are about 11 centimeters, finer than any phone GPS can deliver. Longitude steps are shorter by the cosine of the latitude.
Questions about coordinates
Which comes first, latitude or longitude?
In this tool and in most written coordinates, latitude comes first (north-south, from -90 to 90), then longitude (east-west, from -180 to 180). GeoJSON is the exception and writes longitude first. A letter such as N or W removes any doubt.
What do the negative signs mean?
A negative latitude is south of the equator and a negative longitude is west of the prime meridian. So -33.87, 151.21 is Sydney, in the southern and eastern hemispheres. Do not use both a minus sign and S or W: they say the same thing.
How do I write coordinates so this tool reads them?
Any of these work: 40.7128, -74.0060; 40.7128 N 74.0060 W; 40°42′46″N 74°00′22″W; N 40 42 46 W 74 0 22; and UTM such as 17N 630084 4833438. Use a point for decimals, not a comma.
What datum does it use?
WGS 84, the datum of GPS. The tool does not convert between datums. If your coordinates come from a local national grid or an older datum, convert them to WGS 84 first.
Why does UTM give a zone and a letter?
The zone number (1 to 60) is the 6° strip and the letter is the hemisphere, N or S. Other letters from C to X are latitude bands used by the military grid; this tool reads them but treats letters from N to X as north and C to M as south.
Can it convert coordinates at the poles?
No. UTM covers 80°S to 84°N. Beyond that a different grid (UPS) is used, and the tool says so instead of returning a number.
Sources and limits
- C. F. F. Karney, “Transverse Mercator with an accuracy of a few nanometers”, J. Geodesy 85 (2011) 475–485
The Krüger series (sixth order) used for UTM, with errors under 5 nm within 3 900 km of the central meridian.
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- World Geodetic System (WGS 84)
Semi-major axis 6 378 137 m, flattening 1/298.257223563, semi-minor axis 6 356 752.314245 m.
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- Universal Transverse Mercator coordinate system
Scale 0.9996, false easting 500 km, false northing 10 000 km in the south, the Norway and Svalbard zone exceptions, and the CN Tower example (17N 630084 4833438).
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- OpenFreeMap
No registration, no API keys, no cookies; commercial use allowed; no limits on map views or requests; attribution required.
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- OpenFreeMap terms of service (updated 9 September 2026)
A free service provided as is, with no warranties; automated collection of data without permission is not allowed.
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- OpenStreetMap copyright and license
Map data is under the Open Database License; credit to OpenStreetMap is required.
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These are calculation aids, not survey instruments. They measure on a mathematical model of the Earth (WGS 84); for a legal boundary, engineering or navigation, use a licensed surveyor or the official chart. Nothing you type or load leaves your browser.
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