Convert Decimal Degrees into Degrees, Minutes, Seconds

A map’s geographic coordinates can be given in Decimal Degrees (DD, like 121.135°) or in Degrees, Minutes and Seconds (DMS, like 121°8’6“), which is more common.

Conversion

Basic concept:

  1. The whole units gives the degrees
  2. Multiply the decimal portion by 60; the whole units gives the minutes
  3. Again, multiply the decimal portion multiplied by 60; the whole units gives the seconds
  4. Puts the number together

Formula:

Knowing that 1° = 60' = 3600", let’s say dd = 121.135

  1. d = integer(dd) = 121°
  2. m = integer((dd - d) * 60) = 8’
  3. s = (dd - d - m / 60) * 3600 = 6“

Source: How to Convert Decimal Degrees into Degrees, Minutes, Seconds