Converting National Grid References

Eastings and Northings are measured in hundreds of thousands of metres (100,000 metres). The origin of the National Grid is 000000 (metres) East and 000000 (metres) North. For example, Jedburgh is at NT6520 or 365000 East, 620000 North. However, National Grid references are measured differently, using letters to represent the 100km reference, for example, NS123456. When using the Digimap Gazetteer service, you may need to convert from standard National Grid references to Eastings and Northings.

In a National Grid reference, the letters identify a 100km square and the digits identify a location within that 100km square. The first half of the digits give the Easting, or distance East from the edge of the 100km square. The second half of the digits give the Northing, or distance North from the edge of the 100km square. Notice that there is always an even number of digits - usually 2,4 or 6.

To convert a National Grid Reference to Eastings and Northings:

  1. Remove the two letters at the beginning of the reference: e.g. NS1234 becomes 1234

  2. Split the reference into it's East and North components: e.g. 12 East and 34 North

  3. Work out the numerical reference for the two letters: e.g. NS = 200km East and 600km North.

    Use the diagram below to calculate how many 100km units east and north the bottom left hand corner of your square is. For example, square NS is 200km East and 600km North of the origin, which becomes 2 units East and 6 units North.

  4. Add the appropriate 100km reference to the beginning of the rest of the reference (remembering to omit the letters): e.g. 212 East and 634 North.

  5. Since Eastings and Northings are measured in metres, you will need to add zeros to make the Eastings and Northings of the correct magnitude: e.g. 212,000 Easting and 634,000 Northing.

Examples

More information about the National Grid referencing system can be found elsewhere in these Help pages.