Convert coordinate

Convert geographic coordinates between decimal, DMS, WGS84 Cartesian, and the supported UK grid workflow.

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ToolCoordinate Converter
Input
Output

How it works

Decimal degrees convert to degrees-minutes-seconds, and WGS84 geodetic coordinates become Earth-centred Cartesian values through an ellipsoid. The UK path applies a datum transform and British National Grid projection.

  • WGS84 is the initial global GPS reference.
  • OSGB36 constants are specific to the UK path.

Worked example

Decimal degrees to DMS
51.5074 degrees, the latitude of central London
Input
											Mode: Decimal to DMS
Decimal degrees value: 51.5074
										
Output
												Decimal degrees: 51.5074
Dms formatted: 51 deg 30 min 26.64 sec
Degrees: 51
Minutes: 30
Seconds: 26.64
Os grid reference: 
Easting m: 0
Northing m: 0
											

When to use this

GPS exports change decimal coordinates, UK mapping converts to National Grid, and geodesy lessons compare geodetic and Cartesian coordinates.

Edge cases

  • Antimeridian longitude needs wrapping rather than naïve subtraction.
  • Latitude outside −90° to 90° is invalid.
  • WGS84 and OSGB36 differ by datum, so coordinates cannot be copied between them.

References