How to use the coordinate format converter
- Type the latitude and the longitude. You can use decimal degrees such as 40.446195, degrees and minutes such as 40 26.767 N, or degrees, minutes and seconds such as 40 26 46 N.
- Use a minus sign or the letters N, S, E and W for the direction, but not both together.
- Read the point in all three formats in the table and the headline.
- Press a preset to see an example of each style, then copy or print the result.
Formula
Decimal degrees = degrees + minutes / 60 + seconds / 3600
Degrees = whole part of the decimal value
Minutes = 60 x the fraction left over, whole part
Seconds = 60 x the fraction of the minutes left over
South and west are negative in decimal degrees. Seconds are rounded to two decimals and decimal minutes to four, and a rounded 60 carries into the next unit.
One point in three styles
The decimal point 40.446195, -79.982195 is 40 degrees 26 minutes 46.30 seconds north and 79 degrees 58 minutes 55.90 seconds west. Check: 0.446195 x 60 = 26.7717 minutes, and 0.7717 x 60 = 46.302 seconds. For longitude, 0.982195 x 60 = 58.9317 minutes, and 0.9317 x 60 = 55.902 seconds.
In degrees and decimal minutes the same point is 40 degrees 26.7717 minutes north and 79 degrees 58.9317 minutes west. Typing 40 26 46.3 N and 79 58 55.9 W returns 40.446194 and -79.982194 to six decimals, a difference that comes from rounding the seconds.
Three ways to write the same place
Maps and apps use decimal degrees because they are easy for software. Older charts, surveys and many printed guides give degrees, minutes and seconds, and some navigation gear uses degrees and decimal minutes. The numbers describe the same position, so it is just a matter of changing units, like converting hours into minutes.
Once the points are in decimal degrees, you can measure between them with the Great Circle Distance Calculator, and work out times of arrival with the Flight Arrival Time Calculator.
Common mistakes
Mixing up the order is the most common error. Latitude comes first and runs from -90 to 90, longitude comes second and runs from -180 to 180. A point entered the other way round lands in the wrong place. Another is forgetting that south and west are negative in decimal degrees.
Also check the direction letters: a longitude can end with E or W, and a latitude with N or S. The tool rejects a letter that does not match the field, and rejects minutes or seconds of 60 or more. See also the Time Zone Converter when the place is far from where you are.
Assumptions and limits
- Minutes must be below 60 and seconds below 60, and degrees must be within the range of the field.
- Only the degrees can carry a minus sign, and a direction letter cannot be used with a minus sign.
- The conversion changes the notation only. It does not convert between map datums.
- Everything is calculated in your browser and nothing is sent or stored.
Frequently asked questions
How do I convert degrees minutes seconds to decimal degrees?
Divide the minutes by 60, divide the seconds by 3,600 and add both to the degrees. For 40 degrees 26 minutes 46 seconds, that is 40 + 0.43333 + 0.01278 = 40.44611. Make it negative for south or west.
What does a negative number mean?
A negative latitude is south of the equator and a negative longitude is west of the prime meridian. In degrees, minutes and seconds the same information is written with the letters S or W.
Why does a round trip change the last digit?
Seconds are rounded to two decimals, which limits precision to about a third of a meter. Converting back to decimal degrees can differ in the sixth decimal for that reason.
Can I type a symbol like the degree sign?
Yes. Degree, minute and second marks are accepted, and so are spaces or colons between the parts. The tool ignores the marks and reads the numbers in order.