This is a Java library implementing the Ordnance Survey's OSTN02 conversion, between OS easting/northing (example: 528376.804,180799.396) and what everyone else uses, latitude/longitude (example: 51.511547,-0.151412). In other words, the same conversion as this online converter

        EastingNorthing first = new EastingNorthing(528376.804,180799.396);
        LatitudeLongitude second = first.toLatitudeLongitude();
        EastingNorthing third = second.toEastingNorthing();
        
        System.out.println("First: "+first.getEast()+","+first.getNorth());
        System.out.println("Second: "+second.getLat()+","+second.getLon());
        System.out.println("Third: "+third.getEast()+","+third.getNorth());

Produces:

First: 528376.804,180799.396
Second: 51.51154701260418,-0.15141202586203606
Third: 528376.8020999633,180799.3969603534

We can't do this conversion without using some Ordnance Survey data.

The OSTN02 conversion table data is copyrighted by Ordnance Survey. You can copy it and integrate it into your software, but they require attribution; for more info see this documentation The data is (c) Crown copyright 2002, All rights reserved.

The java files that comprise the rest of this project are (c) Michael Tandy; they are under the MIT license.

I wanted something simple; this project only has 5 classes, and most users will only need two of them - EastingNorthing and LatitudeLongitude.

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