EPSG:27700

OSGB36 / British National Grid -- United Kingdom Ordnance Survey

Transform Get position on a map

Available transformations
to EPSG:4230
EPSG:4230 - ED50

  • United Kingdom (UK) , accuracy 2.0 m, code 1315 (default) [7]

Selected transformation

Method: Position Vector transformation (geog2D domain)

Remarks: Known as the "UKOOA landward/seaward transformation". This transformation is concatenated from OSGB36 to WGS 84 (6) (Petroleum) (code 1314) minus ED50 to WGS 84 (18) (Common Offshore) (code 1311). Accuracy better than 4m and generally better than 2m.

Information source: UK Offshore Operators Association.

Revision date: 2021-03-18

Attributes

Unit: metre

Geodetic CRS: OSGB36

Datum: Ordnance Survey of Great Britain 1936

Ellipsoid: Airy 1830

Prime meridian: Greenwich

Data source: EPSG

Information source: Ordnance Survey of Great Britain.

Revision date: 2021-03-18

Scope: Engineering survey, topographic mapping.

Area of use: United Kingdom (UK) - offshore to boundary of UKCS within 49°45'N to 61°N and 9°W to 2°E; onshore Great Britain (England, Wales and Scotland). Isle of Man onshore.

Coordinate system: Cartesian 2D CS. Axes: easting, northing (E,N). Orientations: east, north. UoM: m.

Covered area powered by MapTiler MapTiler logo
SimpleMap

Center coordinates
308086.75 608847.15

Projected bounds:
-90730.74 -12270.15
682131.03 1247855.65

WGS84 bounds:
-8.82 49.79
1.92 60.94

United Kingdom (UK) - Great Britain - England and Wales onshore, Scotland onshore and Western Isles nearshore including Sea of the Hebrides and The Minch; Isle of Man onshore.
MapTiler banner

Definition: OGC Well Known Text

PROJCS["OSGB36 / British National Grid",
    GEOGCS["OSGB36",
        DATUM["Ordnance_Survey_of_Great_Britain_1936",
            SPHEROID["Airy 1830",6377563.396,299.3249646],
            TOWGS84[535.948,-31.357,665.16,0.15,0.247,0.998,-21.689]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4277"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",49],
    PARAMETER["central_meridian",-2],
    PARAMETER["scale_factor",0.9996012717],
    PARAMETER["false_easting",400000],
    PARAMETER["false_northing",-100000],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AXIS["Easting",EAST],
    AXIS["Northing",NORTH],
    AUTHORITY["EPSG","27700"]]

Definition: OGC Well Known Text 2 (2019)

BOUNDCRS[
    SOURCECRS[
        PROJCRS["OSGB36 / British National Grid",
            BASEGEOGCRS["OSGB36",
                DATUM["Ordnance Survey of Great Britain 1936",
                    ELLIPSOID["Airy 1830",6377563.396,299.3249646,
                        LENGTHUNIT["metre",1]]],
                PRIMEM["Greenwich",0,
                    ANGLEUNIT["degree",0.0174532925199433]],
                ID["EPSG",4277]],
            CONVERSION["British National Grid",
                METHOD["Transverse Mercator",
                    ID["EPSG",9807]],
                PARAMETER["Latitude of natural origin",49,
                    ANGLEUNIT["degree",0.0174532925199433],
                    ID["EPSG",8801]],
                PARAMETER["Longitude of natural origin",-2,
                    ANGLEUNIT["degree",0.0174532925199433],
                    ID["EPSG",8802]],
                PARAMETER["Scale factor at natural origin",0.9996012717,
                    SCALEUNIT["unity",1],
                    ID["EPSG",8805]],
                PARAMETER["False easting",400000,
                    LENGTHUNIT["metre",1],
                    ID["EPSG",8806]],
                PARAMETER["False northing",-100000,
                    LENGTHUNIT["metre",1],
                    ID["EPSG",8807]]],
            CS[Cartesian,2],
                AXIS["(E)",east,
                    ORDER[1],
                    LENGTHUNIT["metre",1]],
                AXIS["(N)",north,
                    ORDER[2],
                    LENGTHUNIT["metre",1]],
            USAGE[
                SCOPE["Engineering survey, topographic mapping."],
                AREA["United Kingdom (UK) - offshore to boundary of UKCS within 49°45'N to 61°N and 9°W to 2°E; onshore Great Britain (England, Wales and Scotland). Isle of Man onshore."],
                BBOX[49.75,-9.01,61.01,2.01]],
            ID["EPSG",27700]]],
    TARGETCRS[
        GEOGCRS["WGS 84",
            ENSEMBLE["World Geodetic System 1984 ensemble",
                MEMBER["World Geodetic System 1984 (Transit)"],
                MEMBER["World Geodetic System 1984 (G730)"],
                MEMBER["World Geodetic System 1984 (G873)"],
                MEMBER["World Geodetic System 1984 (G1150)"],
                MEMBER["World Geodetic System 1984 (G1674)"],
                MEMBER["World Geodetic System 1984 (G1762)"],
                MEMBER["World Geodetic System 1984 (G2139)"],
                ELLIPSOID["WGS 84",6378137,298.257223563,
                    LENGTHUNIT["metre",1]],
                ENSEMBLEACCURACY[2.0]],
            PRIMEM["Greenwich",0,
                ANGLEUNIT["degree",0.0174532925199433]],
            CS[ellipsoidal,2],
                AXIS["geodetic latitude (Lat)",north,
                    ORDER[1],
                    ANGLEUNIT["degree",0.0174532925199433]],
                AXIS["geodetic longitude (Lon)",east,
                    ORDER[2],
                    ANGLEUNIT["degree",0.0174532925199433]],
            USAGE[
                SCOPE["Horizontal component of 3D system."],
                AREA["World."],
                BBOX[-90,-180,90,180]],
            ID["EPSG",4326]]],
    ABRIDGEDTRANSFORMATION["Transformation from unknown to WGS84",
        METHOD["Position Vector transformation (geog2D domain)",
            ID["EPSG",9606]],
        PARAMETER["X-axis translation",535.948,
            ID["EPSG",8605]],
        PARAMETER["Y-axis translation",-31.357,
            ID["EPSG",8606]],
        PARAMETER["Z-axis translation",665.16,
            ID["EPSG",8607]],
        PARAMETER["X-axis rotation",0.15,
            ID["EPSG",8608]],
        PARAMETER["Y-axis rotation",0.247,
            ID["EPSG",8609]],
        PARAMETER["Z-axis rotation",0.998,
            ID["EPSG",8610]],
        PARAMETER["Scale difference",0.999978311,
            ID["EPSG",8611]]]]

Definition: ESRI Well Known Text

PROJCS["British_National_Grid",
    GEOGCS["GCS_OSGB_1936",
        DATUM["D_OSGB_1936",
            SPHEROID["Airy_1830",6377563.396,299.3249646]],
        PRIMEM["Greenwich",0.0],
        UNIT["Degree",0.0174532925199433]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["False_Easting",400000.0],
    PARAMETER["False_Northing",-100000.0],
    PARAMETER["Central_Meridian",-2.0],
    PARAMETER["Scale_Factor",0.9996012717],
    PARAMETER["Latitude_Of_Origin",49.0],
    UNIT["Meter",1.0]]

Definition: PROJ.4

+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +towgs84=535.948,-31.357,665.16,0.15,0.247,0.998,-21.689 +units=m +no_defs +type=crs

Definition: JavaScript (Proj4js) 

proj4.defs("EPSG:27700","+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +towgs84=535.948,-31.357,665.16,0.15,0.247,0.998,-21.689 +units=m +no_defs +type=crs");

Definition: JSON

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "type": "BoundCRS",
    "source_crs": {
        "type": "ProjectedCRS",
        "name": "OSGB36 / British National Grid",
        "base_crs": {
            "name": "OSGB36",
            "datum": {
                "type": "GeodeticReferenceFrame",
                "name": "Ordnance Survey of Great Britain 1936",
                "ellipsoid": {
                    "name": "Airy 1830",
                    "semi_major_axis": 6377563.396,
                    "inverse_flattening": 299.3249646
                }
            },
            "coordinate_system": {
                "subtype": "ellipsoidal",
                "axis": [
                    {
                        "name": "Geodetic latitude",
                        "abbreviation": "Lat",
                        "direction": "north",
                        "unit": "degree"
                    },
                    {
                        "name": "Geodetic longitude",
                        "abbreviation": "Lon",
                        "direction": "east",
                        "unit": "degree"
                    }
                ]
            },
            "id": {
                "authority": "EPSG",
                "code": 4277
            }
        },
        "conversion": {
            "name": "British National Grid",
            "method": {
                "name": "Transverse Mercator",
                "id": {
                    "authority": "EPSG",
                    "code": 9807
                }
            },
            "parameters": [
                {
                    "name": "Latitude of natural origin",
                    "value": 49,
                    "unit": "degree",
                    "id": {
                        "authority": "EPSG",
                        "code": 8801
                    }
                },
                {
                    "name": "Longitude of natural origin",
                    "value": -2,
                    "unit": "degree",
                    "id": {
                        "authority": "EPSG",
                        "code": 8802
                    }
                },
                {
                    "name": "Scale factor at natural origin",
                    "value": 0.9996012717,
                    "unit": "unity",
                    "id": {
                        "authority": "EPSG",
                        "code": 8805
                    }
                },
                {
                    "name": "False easting",
                    "value": 400000,
                    "unit": "metre",
                    "id": {
                        "authority": "EPSG",
                        "code": 8806
                    }
                },
                {
                    "name": "False northing",
                    "value": -100000,
                    "unit": "metre",
                    "id": {
                        "authority": "EPSG",
                        "code": 8807
                    }
                }
            ]
        },
        "coordinate_system": {
            "subtype": "Cartesian",
            "axis": [
                {
                    "name": "Easting",
                    "abbreviation": "E",
                    "direction": "east",
                    "unit": "metre"
                },
                {
                    "name": "Northing",
                    "abbreviation": "N",
                    "direction": "north",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 27700
        }
    },
    "target_crs": {
        "type": "GeographicCRS",
        "name": "WGS 84",
        "datum_ensemble": {
            "name": "World Geodetic System 1984 ensemble",
            "members": [
                {
                    "name": "World Geodetic System 1984 (Transit)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1166
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G730)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1152
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G873)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1153
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G1150)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1154
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G1674)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1155
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G1762)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1156
                    }
                },
                {
                    "name": "World Geodetic System 1984 (G2139)",
                    "id": {
                        "authority": "EPSG",
                        "code": 1309
                    }
                }
            ],
            "ellipsoid": {
                "name": "WGS 84",
                "semi_major_axis": 6378137,
                "inverse_flattening": 298.257223563
            },
            "accuracy": "2.0",
            "id": {
                "authority": "EPSG",
                "code": 6326
            }
        },
        "coordinate_system": {
            "subtype": "ellipsoidal",
            "axis": [
                {
                    "name": "Geodetic latitude",
                    "abbreviation": "Lat",
                    "direction": "north",
                    "unit": "degree"
                },
                {
                    "name": "Geodetic longitude",
                    "abbreviation": "Lon",
                    "direction": "east",
                    "unit": "degree"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 4326
        }
    },
    "transformation": {
        "name": "Transformation from unknown to WGS84",
        "method": {
            "name": "Position Vector transformation (geog2D domain)",
            "id": {
                "authority": "EPSG",
                "code": 9606
            }
        },
        "parameters": [
            {
                "name": "X-axis translation",
                "value": 535.948,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8605
                }
            },
            {
                "name": "Y-axis translation",
                "value": -31.357,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8606
                }
            },
            {
                "name": "Z-axis translation",
                "value": 665.16,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8607
                }
            },
            {
                "name": "X-axis rotation",
                "value": 0.15,
                "unit": {
                    "type": "AngularUnit",
                    "name": "arc-second",
                    "conversion_factor": 4.84813681109536e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8608
                }
            },
            {
                "name": "Y-axis rotation",
                "value": 0.247,
                "unit": {
                    "type": "AngularUnit",
                    "name": "arc-second",
                    "conversion_factor": 4.84813681109536e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8609
                }
            },
            {
                "name": "Z-axis rotation",
                "value": 0.998,
                "unit": {
                    "type": "AngularUnit",
                    "name": "arc-second",
                    "conversion_factor": 4.84813681109536e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8610
                }
            },
            {
                "name": "Scale difference",
                "value": -21.689,
                "unit": {
                    "type": "ScaleUnit",
                    "name": "parts per million",
                    "conversion_factor": 1e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8611
                }
            }
        ]
    }
}

Definition: GeoServer

27700=PROJCS["OSGB36 / British National Grid",GEOGCS["OSGB36",DATUM["Ordnance_Survey_of_Great_Britain_1936",SPHEROID["Airy 1830",6377563.396,299.3249646],TOWGS84[535.948,-31.357,665.16,0.15,0.247,0.998,-21.689]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4277"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",49],PARAMETER["central_meridian",-2],PARAMETER["scale_factor",0.9996012717],PARAMETER["false_easting",400000],PARAMETER["false_northing",-100000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","27700"]]

Definition: MapServer - MAPfile

PROJECTION
	"proj=tmerc"
	"lat_0=49"
	"lon_0=-2"
	"k=0.9996012717"
	"x_0=400000"
	"y_0=-100000"
	"ellps=airy"
	"towgs84=535.948,-31.357,665.16,0.15,0.247,0.998,-21.689"
	"units=m"
	"no_defs"
	"type=crs"
END

Definition: Mapnik

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +towgs84=535.948,-31.357,665.16,0.15,0.247,0.998,-21.689 +units=m +no_defs +type=crs">
	<Layer srs="+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +towgs84=535.948,-31.357,665.16,0.15,0.247,0.998,-21.689 +units=m +no_defs +type=crs">
	</Layer>
</Map>

Definition: SQL (PostGIS)

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 27700, 'EPSG', 27700, '+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +towgs84=535.948,-31.357,665.16,0.15,0.247,0.998,-21.689 +units=m +no_defs +type=crs', 'PROJCS["OSGB36 / British National Grid",GEOGCS["OSGB36",DATUM["Ordnance_Survey_of_Great_Britain_1936",SPHEROID["Airy 1830",6377563.396,299.3249646],TOWGS84[535.948,-31.357,665.16,0.15,0.247,0.998,-21.689]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4277"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",49],PARAMETER["central_meridian",-2],PARAMETER["scale_factor",0.9996012717],PARAMETER["false_easting",400000],PARAMETER["false_northing",-100000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","27700"]]');