Geodetic Co-ordinates
WGS84/ETRS89
Reference for GPS & online
maps of the British Isles
GPS-compatible
Degrees
Lat N
Lon
OSGB36
Used as graticule markings on
Ordnance Survey maps of Great Britain
Not GPS-compatible
Degrees
Lat N
Lon
ED50 (European Datum)
Used as graticule markings for some
international maps of the British Isles
Not GPS-compatible
Degrees
Lat N
Lon
Great Britain National Grid
Grid Ref. [2-letter Square ID]
Used on OS maps since 1952
Sq.EastingsNorthings
e.g.  SU  392  654
Full Co-ordinates
Full ref., used on OS maps since 1945
Eastings m
Northings m
UTM Co-ordinates
ED50 datum (Intl. 1924 ellipsoid)
Used on some international maps of GB
UTM Zone N hemis.
Eastings m
Northings m
Great Britain National Yard Grid
Used on OS small-scale maps 1931-1945
Full Co-ordinates
Eastings yds
Northings yds
War Office Cassini ('WOFO') Grid
Used on War Office maps of Great Britain from the 1920s to the 1940s.
Grid Reference
Sq.EastingsNorthings
e.g. vP 392 654
Full Co-ordinates
Eastings m
Northings m
Cassini (Delamere) Projection
Co-ordinates
Used as the basis for OS small-scale maps of England & Wales from 1870s (+ Scotland from 1920s) to 1945
 ft  of origin
 ft 
Bonne Projection (Scotland)
Co-ordinates
Used as the basis for OS small-scale maps of Scotland from the 1850s to the 1920s.
 ft  of origin
 ft 
OS County Series (Great Britain & Isle of Man)
Used as the basis for large scale maps of Great Britain from the 1850s to the 1950s.
Select county:
Raw Projection Co-ordinates
Projection origin:
 ft  of origin
 ft 
Possible Alternative Counties (click to load results)
Sheet Co-ordinates (derivative sheets are not guaranteed to exist)
6-inch Full Sheets
Sheet
 scale ft from W edge
 scale ft from S edge
6-inch Quarter Sheets
Sheet  
 scale ft from W edge
 scale ft from S edge
1:2500 Sheets
Sheet . 
 scale ft from W edge
 scale ft from S edge
OSTN02 enabled

Page last updated: 4 May 2009
Build Version: 1.2.003