DMS to Decimal Degrees Calculator

DMS to Decimal Degrees Calculator

Older maps, survey documents, and navigation systems often record coordinates in Degrees-Minutes-Seconds (DMS) format - modern GPS devices and mapping software almost universally use decimal degrees instead. This calculator converts between the two.

Decimal Degrees = Degrees + (Minutes/60) + (Seconds/3600), negative if South or West

Example

40┬░ 42' 46" N:

Decimal Degrees = 40 + (42/60) + (46/3600) = 40.712778┬░

Why This Conversion Comes Up So Often

Anyone working with coordinates pulled from historical documents, land surveys, older GPS units, or nautical charts will regularly need to convert between these formats before using them in modern web mapping APIs or GPS apps, all of which expect decimal degrees as standard input.

A Quick Sanity Check

One minute of latitude is always exactly 1/60th of a degree everywhere on Earth, and one second is 1/3600th of a degree - this makes DMS a naturally hierarchical, sexagesimal (base-60) system inherited from ancient Babylonian angular measurement conventions, the same base-60 system that also gives us 60 minutes in an hour and 360 degrees in a circle.