How DMS and decimal degrees relate
Latitude, longitude and survey angles are often written as 37° 30′ 15″, which is called DMS notation. Mapping apps and spreadsheets instead expect decimal degrees such as 37.504167°. One degree holds 60 minutes and one minute holds 60 seconds, so the conversion is simple arithmetic: divide the minutes by 60, divide the seconds by 3600 and add both to the whole degrees.
Going the other way, multiply the fractional part of the decimal value by 60 to get minutes, then multiply what is left by 60 again to get seconds. This converter handles both directions and shows seconds with two decimals. When rounding pushes the seconds to exactly 60, it carries them into the minutes and, if needed, the minutes into the degrees, so a result never reads 59′60″. The carry row appears only when a carry actually happened.
For south latitude and west longitude the sign belongs to the degrees alone, so the DMS side takes a separate sign selector and absolute values for the numbers. On the decimal side you simply type a leading minus. Every result also lists the total in minutes, the total in seconds and a round-trip check that converts the answer back to decimal degrees, which makes a typo easy to spot. Radian and gradian conversion is not supported.
Frequently Asked Questions
One degree is 60 minutes and one minute is 60 seconds, so one degree holds 3600 seconds. To get decimal degrees, divide minutes by 60 and seconds by 3600, then add both to the degrees.
Pick the negative sign option (S or W) and type degrees, minutes and seconds as absolute values. The sign belongs to the degrees only, never to minutes or seconds.
Rounding seconds to two decimals can push them to exactly 60. This converter carries 60 seconds into 1 minute and 60 minutes into 1 degree, so that notation never appears.