Mercator from Midnight Oil Software
Mercator is a useful windows program for converting between Latitude & Longitude
and Ordnance Survey grid references
and vice versa.
As you can see, it's very easy to use.
Latitude/Longitude to Grid
When converting from Lat/Long to OS grid refs you can select the number of
figures to be calculated ranging from 2 to 14.
The accuracies involved are as follows:
| Figures |
Accuracy |
| 2 |
10km |
| 4 |
1km |
| 6 |
100m |
| 8 |
10m |
| 10 |
1m |
| 12 |
10cm |
| 14 |
1cm |
Grid to Latitude/Longitude
To make the conversion from lat/long to grid refs simply type in the degrees,
minutes and seconds and select East or West after the longitude.
Decide on the required accuracy and then just press
the 
button to see the results.
Press 
to empty the input fields.
Converting from grid refs to lat/longitudes is even simpler - you just type in
the grid reference, including the 2-letter prefix, using as many figures as you
want, and press .
Cartography Links
GPS Links
Ordnance Survey
Convert Geographic coordinates to Lambert
ERIN Spatial Data Management System - Contents
GSC Magnetic Declination
EPS - The Elgaard Positioning System
On-Magazine
Antiquarian Maps at Mercator's World (no relation!)
Ptolemy's World Map, c. 150 AD
Midnight Oil Software
Chris's Ballooning Page
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