This free decimal degrees to DMS converter turns a latitude or longitude number into degrees, minutes and seconds, and converts DMS to decimal degrees just as quickly the other way. Enter a decimal coordinate and you get the DMS value, the degrees-and-decimal-minutes (DDM) value and the correct hemisphere letter instantly. No login, no upload, everything runs in your browser.
Use a minus sign for southern latitudes and western longitudes, e.g. -77.0365.
Please enter a valid number between -180 and 180.
A coordinate in decimal degrees packs the whole angle into one number. DMS splits that same angle into three sexagesimal units, because the traditional system divides one degree into 60 minutes and one minute into 60 seconds.
Going from decimal degrees to DMS is a two-step extraction. First, the part of the number
before the decimal point is the degrees. Second, multiply the remaining fraction by 60 to
obtain the minutes; the whole part of that result is the minutes, and multiplying the leftover
fraction by 60 once more gives the seconds. For example, 39.906111° yields
39° 54′ 22.00″. The reverse direction simply adds the parts back together:
decimal = degrees + minutes / 60 + seconds / 3600.
The hemisphere letter is not part of the arithmetic — it is carried by the sign. Negative
latitude is south (S) and negative longitude is west (W). Because degrees, minutes and seconds
are base-60, rounding the seconds field can push the value up to the next minute or degree;
this converter accounts for that carry so you never see an invalid result such as
60″.
The method is easiest to follow on a real number. Take the latitude 39.906111° in the
northern hemisphere: the whole part, 39, is the degrees; multiply the leftover 0.906111 by 60 to
get 54.36666, so 54 is the minutes; multiply the remaining 0.36666 by 60 to get 22.00 seconds.
The answer is 39° 54′ 22.00″ N.
A negative value simply adds the hemisphere at the end. For the longitude −77.0365°,
work with the absolute value 77.0365 and apply the sign as W: 0.0365 × 60 = 2.19 minutes, leaving
0.19 × 60 = 11.40 seconds, giving 77° 02′ 11.40″ W. The table below lists values the
converter produces — you can type any of them into the box above to check the rounding yourself.
| Decimal degrees | Hemisphere | DMS | DDM |
|---|---|---|---|
| 39.906111 | N | 39° 54′ 22.00″ | N 39° 54.367′ |
| −77.0365 | W | 77° 02′ 11.40″ | W 77° 02.190′ |
| −0.1276 | W | 0° 07′ 39.36″ | W 0° 07.656′ |
| 116.3974 | E | 116° 23′ 50.64″ | E 116° 23.844′ |
The calculator's default is two decimal places on the seconds; the DDM column is shown to three decimal places on the minutes, as most charts are.
The reverse direction — DMS to decimal degrees — is a single sum rather than a repeated
multiplication: decimal = degrees + minutes / 60 + seconds / 3600. Applied to
39° 54′ 22.00″ it gives 39 + 54/60 + 22/3600 = 39.906111. Watch the sign: for southern latitudes
and western longitudes the whole result is negative, so 77° 02′ 11.40″ W becomes
−77.0365.
In the DMS → Decimal tab above you can type the degrees, minutes and seconds directly and pick the hemisphere; the converter applies the sign for you and returns the decimal degree value at the precision you set.
Degrees and decimal minutes (DDM) is the third common format: a whole degree value plus minutes
carried to several decimal places, such as N 39° 54.367′. It is standard in marine
charts, in aviation and in many older GPS receivers. All three formats — DD, DMS and DDM —
describe the same point, so conversion is lossless provided you keep enough decimal places.
The converter shows all three side by side, so you can copy whichever one the device, chart or document expects without re-entering the coordinate.
You typically need a decimal degrees to DMS conversion when the format a device or document expects differs from the one you hold. Common cases include:
Take the whole number as degrees. Multiply the decimal fraction by 60 for minutes, then multiply the remaining fraction by 60 again for seconds. Example: 39.906111 becomes 39° 54′ 22.00″.
Decimal degrees express a coordinate as one decimal number such as 39.906111. DMS expresses the same angle in degrees, minutes and seconds such as 39° 54′ 22.00″. GIS and databases usually store DD; survey plans and map labels often use DMS.
A negative value is south of the equator for latitude, or west of the prime meridian for longitude. So −39.906111 is 39° 54′ 22.00″ S, and −77.0365 is 77° 02′ 11.40″ W. The hemisphere letter is applied automatically.
DDM is degrees and decimal minutes, such as N 39° 54.367′. It is common in marine and aviation navigation. Use it when a chart or device expects decimal minutes instead of seconds.
The tool uses double-precision arithmetic, and you can set the seconds to as many as 6 decimal places. Seconds to 4 decimal places is 0.0001 of a second, about 3 mm on the ground at the equator — far finer than consumer GPS accuracy.
It is free, with no login, no account and no limit. The calculation runs entirely in your browser, so no coordinate is ever sent to a server.
Add the parts together: decimal = degrees + minutes ÷ 60 + seconds ÷ 3600. For example, 39° 54′ 22.00″ becomes 39 + 54/60 + 22/3600 = 39.906111. For southern latitudes and western longitudes the result is negative.
Calculations run locally in your browser. Verify critical coordinates against your project's coordinate reference system before use in the field. About · Privacy & cookies · Terms of use · Developers