GPS Coordinate Format - What say you?

Windrift.Adventure

Rank V
Launch Member
Member

Enthusiast III

1,626
Darby, Montana, USA
First Name
Tracy
Last Name
000
Member #

15050

Ham/GMRS Callsign
K7MTP
  • What's your flavor?

  • Degrees, minutes, and seconds (DMS): Example = 41°24'12.2"N 2°10'26.5"E
  • Degrees and decimal minutes (DMM): Example = 41 24.2028, 2 10.4418
  • Decimal degrees (DD): Example = 41.40338, 2.17403
Seems like most folks in the overland community use the Decimal Degrees system and I would assume because it's easier to input coordinate data into various devices/programs. Having a military/LEO/aviation background I've use all three including the MGR /GZD method but I'm curious what others like to use.

I've often wondered if the DD method is generally accepted in the overland community just through osmosis or if there's been somewhat of an official edict declared by the Overland King who said, "By royal decree, and in order to unite all of the people throughout the land; all terrestrial explorers in the Kingdom of Overlandia shall henceforth use decimal minutes. Dilly Dilly!"

*** I originally (unintentionally) posted this in a different forum section so I'm reposting here so that it's more appropriately indexed.
 
I prefer DMS since that is what I use at work, but decimal degrees are easy to understand and say quickly. UTM and MGRS always take like 7 years to say the whole location so I don't like those.

I always laugh when I see people giving out coords in any format down to inches. Unless you're looking for a very very specific location then even just 10m accuracy is good enough.
 
From my years of SAR experience mostly UTM. Most of the county SO's use it for that purpose here in the PNW. The good part though is use what you know best, but be knowledgeable in all others..being well rounded has its benefits
 
Last edited:
The beauty of UTM is it's essentially a metric system. It uses a 1000 meter grid broken down into 100 meters and 1 meters. Fortunately that's reasonably translatable to yards and feet also and easy enough to eyeball on a gridded map.
 
Being a rotor wing guy we use degrees decimal minutes in the machine. But with the tech today it’s very easy to jump between datum and formats. Gaia, Avenza, GE etc. Good to see the different responses.
 
I help make maps of other planets and help point instruments at those planets. We use DD.

There are a lot of reasons why. These days, it's as much historical as anything else, but it used to do with ease of software development and compute power: any particular location is easily identified by a simple pair of floating point numbers. If necessary, we can tell the computers how to translate DMS and DMM into and out of DD, but in the end, they use radians for all of the calculations; translation from DD to radians is super simple. Back in the early days of space exploration, even the computers on Earth weren't exactly powerful, so having extra steps to translate from DMS or DMM meant wasted computations, wasted power, wasted heat, wasted time. On the spacecraft themselves, all of our coordinate system rotations and translations work better on simple floating point numbers (radians for angles) and the fewer wasted FPGA calculations the better, so we send radians up and receive radians in the telemetry streams.
 
  • Like
Reactions: Aaron Niemi
I'm a rotory wing guy for the Army, so we almost exclusively use MGRS. However, search and rescue usually use DMS, so I've had to learn both as MGRS and DMS have their benefits.

At the end of the day, use a system that makes sense and is used by search and rescue in the event of an emergency.
 
I’m a UTM/USNG guy. I am very good with MGRS but it’s not really used outside of .mil This year the National Association for Search and Rescue officially adopted USNG. USNG is the same as MGRS CONUS and surrounding territories until you go to NAD 27 DATUM.

USNG has been adopted by DHS for cross departmental interoperability.
 
  • What's your flavor?

  • Degrees, minutes, and seconds (DMS): Example = 41°24'12.2"N 2°10'26.5"E
  • Degrees and decimal minutes (DMM): Example = 41 24.2028, 2 10.4418
  • Decimal degrees (DD): Example = 41.40338, 2.17403
Seems like most folks in the overland community use the Decimal Degrees system and I would assume because it's easier to input coordinate data into various devices/programs. Having a military/LEO/aviation background I've use all three including the MGR /GZD method but I'm curious what others like to use.

I've often wondered if the DD method is generally accepted in the overland community just through osmosis or if there's been somewhat of an official edict declared by the Overland King who said, "By royal decree, and in order to unite all of the people throughout the land; all terrestrial explorers in the Kingdom of Overlandia shall henceforth use decimal minutes. Dilly Dilly!"

*** I originally (unintentionally) posted this in a different forum section so I'm reposting here so that it's more appropriately indexed.
I am more of an 8-digit-grid kind of guy, the problem is it's so difficult to get topo maps these days and GPS is often useless on the trail.
 
I decree, royally, DD will be the format we use!
 
Thank you, for all the great information this post contains! The complete answers, with the reason why, is great. I am learning much from this. I think this has great value and should be saved? Looking forward to more answers! Vance.