ESRI:102400 · United Kingdom
London Survey Grid to KML & KMZ
London Survey Grid (ESRI:102400) is a Transverse Mercator coordinate system on the London Survey Grid datum, with coordinates in metres. Its official area of use is: UK - London.
- Converter already set to ESRI:102400
- Latitude and longitude on WGS 84, as Google Earth uses
- Download the point as KML
Loading converter…
Good to know
- Datum: Treated as WGS 84, no shift (the datums agree to about a metre or better).
Convert a whole spreadsheet
- Open the web app or the Windows app, and paste your rows from Excel or open a CSV file.
- Under Coordinate system, search for “102400” and pick London Survey Grid.
- Check one point you know on the map, then press Save KML or Save KMZ and open it in Google Earth.
Common mistakes with London Survey Grid
- Feet entered as metres. London Survey Grid is in metres. Coordinates copied from a drawing in feet must be converted first, or every point moves outwards from the grid's origin.
- Forgetting the datum. London Survey Grid is not on WGS 84: treated as WGS 84, no shift (the datums agree to about a metre or better). Picking a WGS 84 grid with the same projection instead leaves the points off by that amount.
- Points outside the grid's area. London Survey Grid is meant for UK - London. Points well outside that area convert with growing error; the converter flags them so you can choose the right grid.
- A local site grid. If every point is off by the same distance and direction, the drawing may be on a local site grid. Calibrate on three or more known control points instead.
New to this? Read how to convert easting and northing to latitude and longitude.