Anyone working on Garmin NT compiler?

There is an significant increase in OSM map data which is great. But, with that increase in data comes a price. My GPS can only load 4000 tiles and/or 4GB of map data. If I want all of the US or EU on my GPS there is no way with the current mkgmap. Is anyone working on a compatible Garmin NT compiler?


To the best of my knowledge Garmin have encrypted the NT format to prevent it from being reverse engineered. Unless they change their policy there won’t be any free NT maps.

The best way forward for us as a community is to move to an open platform and write our own navigation software. Moves in that direction are already afoot.

Yes, but this will not be Garmin. For Android we already have some good software.

And outdoor-proof Android-devices are already existing.

Officially, Garmin supports free(osm) maps. At least they have a free-maps board in their
official forums. But anyway, when they would open the file formats, other commercial
map makers would be competitional to garmin own maps. So, I think they will keep them closed.

For me outdoor-proof means:

  • runs with AA-batteries and with one charge more then 15h
  • display useful also while sun is shining
  • robust bicyclemount
  • stable software and hardware

Also it must be possible to create my own maps.

“Garmin Custom Maps” are georeferenced raster maps. That’s the main direction of that forum. Occasionally vector map questions get posted there, but that’s not the main focus.
That said, some of the developers present on the BaseCamp forum have been surprisingly helpful.

Let’s come back to the 4GB limit. Presently, map makers try to put “all” available data into their maps, and thus maps in well mapped regions become very big. But do you really need all that information in your map? When you need a map for navigation in your car, that will work as well without showing buildings. You can also omit agricultural tracks and hiking trails. Some people also like to hide industrial areas, forests, etc. Several “points of interest” can also be omitted. “Selection” instead of “inclusion” is the way to go.