Maidenhead grid for Google Earth by OH2ECG
On this page you can download a simple Windows program that will create an
overlay for Google Earth
that displays a 6-character deep version of the
Alternatively you can download a smaller
ready-to-use KMZ-file covering the Maidenhead grid only to
4-character deep level.
The Maidenhead grid is used extensively by
to easily provide location information in a very condensed form. This
overlay grid gets more detailed as you zoom in to the
Google Earth display and it covers the grid down to the subsquare
level, ie. from field (for example KP) and square
(for example KP20) to subsquare (for example KP20JI).
Using the software
Note: If you are not interested in the large 6-character version of the
grid overlay and are happy with the smaller 4-character version, you can
skip a majority of the following chapters and go directly to
"Disclaimers" and the download links after that.
The software is delivered as a single executable
MaidenheadGridByOH2ECG.exe. Download the software to an empty
directory on your computer using the link at the end of this page.
Even though the software itself is very small, you will need roughly
22 gigabytes of free space on your harddrive to store all the files
created while running it. There are methods to decrease the amount of
required disk space afterwards though, please see the Tips-section after
Double click the downloaded file or use your preferred method to start
the software. Once the program is started, it will display the progress in
a console window similar to this:
The progress is shown as field values going from AA to RR, ie. the complete
range of Maidenhead grid field values. Depending on your computer it may
take a long time for the program to complete. On my 3.2 GHz Core2 Duo
processor equipped computer it takes roughly 20 minutes.
If you ran the program in a command window, you'll see this kind of messages
in the end:
If you ran it by double clicking the executable in Windows
Explorer, the console window will simply be closed upon completion.
Loading the grid to Google Earth
Once the program has finished, start your Google Earth software and
use the File / Open command to open a kml file. Browse to the
directory where you saved and ran the MaidenheadGridByOH2ECG.exe
program. In this directory you will find a new kml file named
MaidenheadGridByOH2ECG.kml. Select and open that. Now it will
take a few seconds for Google Earth to load the file. When it is done,
you will see the globe like this:
Spin and zoom the globe as you like and approach your point of interest.
When you zoom close enough, you will see 4-character squares inside the
Zooming even further down you will see the 6-character subsquares:
Loading individual squares
If you are not interested in global grid coverage, you can simply open
one or more squares from the sq subdirectory created by the program.
Each of the 32400 squares around the globe are present there in a
correspondingly named kml file.
This software is purely a personal contribution, it is not a product of
Finnish Steel Design Trading Ltd.
I've created this software as a programming exercise to get myself
familiar with the kml file format. I provide this software free of charge
to the ham radio community and other parties who may find it interesting
or useful. There is no support and absolutely no guarantees for this software.
You are free to use this software for any purpose be it personal, academic
or commercial as long as you understand and comply with all the conditions
presented in this section ('Disclaimers'), otherwise you are not allowed
to download or use this software.
These terms apply to the software available for public download at the
moment. The terms of possible future versions of this software may change
at any time without prior notice.
Download the software
Please read the disclaimers in the above section first. Once you've read
and agreed to them you can download the latest version of the grid
overlay software from here:
Download Maidenhead grid for Google Earth by OH2ECG v1.1 (45 kilobytes)
Alternative smaller ready-to-use version
If you only need 4-character locator coverage, you can download this
alternative ready-to-use kmz-file:
Download smaller 4-character Maidenhead grid for Google Earth by OH2ECG (1 megabyte)
- Reducing the amount of required diskspace afterwards:
- Compress the whole directory structure created by the software into
a single ZIP-file, for example grid.zip and rename that to
grid.kmz. This way the data covering the whole globe will
take only about 770 MB of disk. Google Earth will be able to
open this KMZ-file directly, although with some performance
loss. Unfortunately 770 MB is still too large for me to include
on this page as a ready-to-use downloadable file, so you'll have
to make it yourself.
- Remove squares you're not interested in from the sq-subdirectory
created by the software. Google Earth will still show everything
down to the 4-character level but will not show the 6-character
subsquares inside those removed squares.
- Combine the above two methods to create a minimum size compressed
KMZ-file suited best for you.
If you have any comments about this software, you're welcome to e-mail
me to firstname.lastname@example.org. If you are
a ham radio operator and find it useful, your paper QSL card via the bureau
as a simple greeting without QSO info would be appreciated.
- 2015-02-28: V1.0 - First public release
- 2017-01-05: V1.1 - Removed illegal 'extra' subsquares. Thanks to Terry WQ7A for spotting this error.
- 2017-07-08: Added alternative smaller 4-character 'ready-to-use' kmz-file requested by Steve G1YBB
- 2018-01-09: Added some instructions and tips.
9th January 2018
73 de Ari Paananen OH2ECG