Distance and Bearing Calculator by Tom OH2FRM

     Copyright © 2025 Tom Ahola www.tomahola.com Also see: APRS.fi

Instructions: Enter locator or coordinates for your station location and the DX (remote) station location to find out bearing and distance from your station to the DX station. Press the SWAP button to swap station locations and you find the bearing in the return direction. If your device has positioning capabilities you can enable Track GPS to update your position automatically. If you would like to know where you end up if you go a certain distance in a certain direction, you can fill in the distance and bearing fields and the DX station position will show just that. Note! a calculation might only take place after you enter a new value and either click outside the text box or press enter, depending on your browser.

The locator is a maidenhead locator and locator lengths of 4, 6, 8 and 10 can be input. You can type latitudes and longitudes in many formats and you can omit the degree, minutes and seconds special symbols and use space instead. Here are some examples:

N60.456    = N60.456°
W95 37.456 = W95°37.456'
S25 40 34  = S25°40'34"
E127 37.4  = E127°37.4'

You can enable a map view separately for your location and the DX location. The map view will update to show the locations. A square will show the size of the given locator square if you input a maidenhead locator. Buttons below the map enables you to center the map at the location, zoom in/out and zoom to three preset zoom levels (3=country, 9=city, 15=street zoom levels). You can drag the map to move around. Also, you can click on the map to set the position.

Since the beginning of this web application it featured a map. As I worked at Nokia at the time, I created the map using the Nokia maps, which was owned by Nokia then. Later it was renamed to HERE maps and Nokia sold the Here maps to a german automobile consortium. Some time after that I was contacted by a very unfriendly 3rd party company, who wanted me to either pay or stop using the maps, although I had chosen the service option that was free for small limited map server traffic. I disabled the map feature for some years due to this hostility. Now the map is up and running again using the nice OpenStreetMaps and the great Leaflet library.

Hope you enjoy and find my little tool useful!
Copyright © 2025 Tom Ahola www.tomahola.com

My station
Track GPS:
Latitude:
Longitude:
Locator:
Enable Map:
zoom:
Remote DX station
 
Latitude:
Longitude:
Locator:
Enable Map:
zoom:
Distance (km):
Bearing (deg):