A few years ago I found myself just south of Paris, France one Sunday with a car and the inclination to do some sight-seeing. Since I was alone and don’t speak French my saving grace was Google Earth and a Tom Tom GPS navigation device.
Tom Tom allows GPS coordinates to be entered as a destination, but Google Earth lists those coordinates in a different format. In researching this article I found out that GPS coordinates can be presented in at least four different formats, making it difficult to understand the coordinates.
Google Maps view of the Eiffel Tower
Click the x to remove the Address box and show the interactive Google Map.
Use Excel to Convert GPS Coordinates for Tom Tom
One of my destinations was to see the Eiffel Tower and Google Earth shows the GPS coordinates to be 48 degrees 51 minutes 32.64 seconds North and 2 degrees 17 minutes 34.90 seconds East. (Coordinate formatting shown as 48° 51′ 29.69″ N 2° 17′ 38.02″ E in Google Earth while holding the mouse over a position on the map.)
However the Tom Tom GPS device wanted coordinate input in degrees only, where minutes and seconds represent the fractional part. So I created a quick spreadsheet to do the conversion. (Click the picture to download the .xls file.)
To convert from Degrees, Minutes, Seconds to a Tom Tom degree format, the math is:
This allowed me to enter GPS coordinates directly into the Tom Tom GPS device. Since I wasn’t familiar with the street names or the numbering system for locating addresses on the Tom Tom, this was much faster than trying to find the correct address in the Tom Tom street directory. The Tom Tom GPS was a loner from an associate so that was another factor in my decision to use GPS coordinates.
Note: Tom Tom allows different formats for GPS coordinates, this example just mirrored settings for the GPS I was using at the time.
Use Excel to Convert GPS Coordinates for Garmin
When I got back home to the USA and tried this with my Garmin it didn’t work because the required format for GPS coordinates was different. My Garmin GPS device wanted Degrees and Minutes only, with seconds being the fractional part of minutes. That formula is different because it requires some concatenation with an empty space between degrees and minutes.
Degrees & ” ” & Minutes+Seconds/60
So my Excel spreadsheet helped me convert numerous GPS coordinates for my trip to Paris.
Note: If you’re wondering about the North and East designations, click this link to see how to read GPS coordinates.
Convert GPS Coordinates with Excel
Here’s an interactive worksheet that you can use to figure out some GPS coordinates for yourself.
To download the worksheet using this link.
Cross-posted at vlatte.net.