Latitude and longitude to Easting/Northing example
51.488865, -0.014573537942, 178526Why convert to Easting and Northing?
Easting and Northing values are the native language of UK surveying, construction, planning, and GIS. They are measured in metres on a flat grid, making them ideal for calculating distances, areas, and bearings without the complications of spherical geometry that come with latitude and longitude.
Planning applications, CAD drawings, engineering specifications, and Ordnance Survey datasets all expect or produce Easting/Northing coordinates. Converting from lat long puts your data into the format these workflows require.
How the conversion works
The converter first transforms the WGS84 latitude and longitude to the OSGB36 datum used by Ordnance Survey. It then applies the British National Grid Transverse Mercator projection to produce the Easting and Northing in metres. The Easting measures the east-west position and the Northing measures the north-south position, both relative to the grid origin southwest of the Isles of Scilly.
For a point in central London, the output is typically around 530,000 E, 180,000 N. The further north and east the location, the larger the values.
When you need this conversion
- Entering a GPS-captured site location into a planning application or CAD drawing.
- Adding a point to a GIS project that uses British National Grid (EPSG:27700) as its coordinate reference system.
- Calculating distances or areas between points using simple metre-based arithmetic.
- Preparing survey data for a report that follows British mapping conventions.
- Combining international lat long data with an existing UK Easting/Northing dataset.
Before you convert
- Confirm the location is within Great Britain - British National Grid covers England, Scotland, and Wales only.
- Check that latitude comes first and longitude comes second in your source data.
- If the source is in DMS or DDM format, CoordinateMapper auto-detects it without manual pre-conversion.
- The output values sit on the OSGB36 datum. CoordinateMapper applies the WGS84-to-OSGB36 transformation as part of the conversion.
How to convert with CoordinateMapper
- Enter your latitude and longitude (e.g. 51.488865, -0.014573) into the converter.
- The parser identifies the format and calculates the British National Grid Easting and Northing.
- Verify the output values fall within expected ranges for your area of Great Britain.
- Copy the Easting and Northing for use in planning applications, CAD, GIS, or survey documents.
Common mistakes
- Reversed coordinates: entering longitude before latitude produces Easting/Northing for a completely different location.
- Location outside Great Britain: points outside England, Scotland, or Wales produce values that fall outside the valid BNG range and are meaningless in a British context.
- Assuming WGS84 equals OSGB36: without the datum transformation, the Easting and Northing can be offset by up to 120 m from the correct position - invisible in the numbers but very real on the ground.
Takeaway
Lat long to Easting/Northing conversion transforms globally portable GPS coordinates into the metre-based grid values that UK professionals rely on. The projection and datum shift are handled automatically - enter your coordinates, check the output, and use it wherever British National Grid values are required.
Sending these to CAD?
If you're converting GPS coordinates into eastings and northings for a drawing, CoordinateMapper Pro exports the results as DXF, with points and labels placed on their own layers, ready to reference in.
See what Pro includes