GPS Coordinates (Latitude and Longitude) are expressed in these two most used formats:
1. Degrees, Minutes, Seconds = A standard example of GPS coordinates in Degrees, Minutes, and Seconds (DMS) format is 48°51′30.24″N, 2°17′40.2″E
2. Decimal Degrees = Express a geographic location using simple positive or negative numbers instead of degrees, minutes, and seconds. -33.8568, 151.2153
For example, using the website: https://www.levinecentral.com/ham/grid_square.php, and entering either your Call Sign or address,
<----- one gets results shown to the left.
The Latitude and Longitude on this website are given in both Decimal Degrees and Degrees-Minutes-Seconds. In addition, you are given your 6-character Maidenhead Grid.
In this case, using KM6RFB, the results are:
Decimal Degrees Degrees-Minutes-Seconds
Latitude: 38.902121 38° 54' 7" N
Longitude: -121.282449 121° 16' 56" W
Convention is that North Latitude is positive while South Latitude is negative; East Longitude is positive while West Longitude is negative.
You can use the website: https://www.directionsmag.com/site/latlong-converter/ to convert from one system to another.
How to Convert Decimal Degrees to DMS
Follow these steps to convert decimal degrees to DMS:
1. For the degrees, use the whole number part of the decimal.
2. For the minutes, multiply the remaining decimal by 60. Use the whole number part of the answer as minutes.
3. For the seconds, multiply the new remaining decimal by 60,
Example: Convert decimal degrees 156.742 to degrees minutes seconds
• The whole number is degrees. So, 156.742 gives you 156 degrees.
• Multiply the remaining decimal by 60.
• 0.742*60 = 44.52, so the whole number 44 equals minutes.
• Multiply the remaining decimal by 60.
• 0.52*60 = 31.2, so the whole number 31 equals seconds.
• Decimal degrees 156.742 converts to 156 degrees, 44 minutes and 31 seconds, or 156° 44' 31".
• Be sure to follow math rules of rounding when calculating seconds by hand. If your resulting seconds is something like 31.9 you may round up to 32.
How to Convert DMS to Decimal Degrees
Decimal degrees = Degrees + (Minutes/60) + (Seconds/3600)
For example, to convert 39° 25' 30" to decimal degrees.
1. First, convert minutes and seconds to their degree equivalents and add the results 25'/60 = 0.4167° 30"/3600 = .0083° and 0.4167° + 0.0083° = 0.425°
2. Then, add this number to the number of degrees. 39° + 0.425° = 39.425°
3. So, the final result is: 39° 25' 30" = 39.425°