OS Grid Reference Display and Analysis


  • Drag the red marker to display the grid reference of its location.
  • Or enter a grid reference in the box below and press Find.

Enter a grid ref with letters and without spaces (e.g. SP1097, SP105975), up to a maximum of 8 digits. Always include the first two letters. A 500m square can be shown by adding "SW", "SE", "NW" or "NE" to a four digit grid ref (e.g. SP1097NE).

The marker will always settle at an intersection in an OS grid spaced at   metres. Grid references are shown below, with correspondingly coloured grid squares on the map.

Show 10m square (8 digit grid ref):  

Show 100m square (6 digit grid ref):  

Show 500m square (4 digit + 2 letter grid ref):  

Show 1km square (4 digit grid ref):  

Show 10km square (2 digit grid ref):  

Show WGS84 longitude and latitude:  


Marker Controls

Credits This mapping tool is based on two libraries of Javascript code. Conversion between OS and other coordinate systems uses code written by Jonathan Stott. The original version of the code which interfaces with the Google maps API was written by Keith Balmer (as used on the Bedfordshire Natural History Society web site), and has been updated to use version 3 of the Google maps API by Peter Coxhead. All code is available under the GNU General Public License Version 2.
Page maintained by Peter Coxhead. Content last updated 17:42, 24 September 2023. Javascript version