EPSG:29903

TM75 / Irish Grid

Available transformations
to EPSG:4258
EPSG:4258 - ETRS89

Selected transformation

Method: Position Vector transformation (geog2D domain)

Remarks: TM75 is based on the geodetic datum of 1965 which should not be confused with the mapping adjustment of 1965 (TM65). May be taken as approximate transformations TM75 to WGS 84, TM65 to WGS 84 and OSNI 1952 to WGS 84 - see codes 1954, 1641 and 1955.

Information source: Ordnance Survey Ireland via EuroGeographics; http://crs.bkg.bund.de/crs-eu/

Revision date: 2023-01-17

Attributes

Unit: metre

Geodetic CRS: TM75

Datum: Geodetic Datum of 1965

Ellipsoid: Airy Modified 1849

Prime meridian: Greenwich

Data source: EPSG

Information source: Ordnance Survey of Ireland

Revision date: 2001-11-06

Scope: Engineering survey, topographic mapping.

Remarks: Replaces both OSNI 1952 / Irish National Grid (code 29901) and TM65 / Irish Grid (code 29902) from 1975. Replaced by IRENET95 / Irish Transverse Mercator (code 2157) from 1/1/2001.

Area of use: Ireland - onshore. United Kingdom (UK) - Northern Ireland (Ulster) - onshore.

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

Center coordinates
203374.16 239960.74

Projected bounds:
21861.71 15177.48
385198.22 468039.71

WGS84 bounds:
-10.56 51.39
-5.34 55.43

Ireland - onshore. United Kingdom (UK) - Northern Ireland (Ulster) - onshore.
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Definition: OGC Well Known Text

PROJCS["TM75 / Irish Grid",
    GEOGCS["TM75",
        DATUM["Geodetic_Datum_of_1965",
            SPHEROID["Airy Modified 1849",6377340.189,299.3249646],
            TOWGS84[482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4300"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",53.5],
    PARAMETER["central_meridian",-8],
    PARAMETER["scale_factor",1.000035],
    PARAMETER["false_easting",200000],
    PARAMETER["false_northing",250000],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AXIS["Easting",EAST],
    AXIS["Northing",NORTH],
    AUTHORITY["EPSG","29903"]]

Definition: OGC Well Known Text 2 (2019)

BOUNDCRS[
    SOURCECRS[
        PROJCRS["TM75 / Irish Grid",
            BASEGEOGCRS["TM75",
                DATUM["Geodetic Datum of 1965",
                    ELLIPSOID["Airy Modified 1849",6377340.189,299.3249646,
                        LENGTHUNIT["metre",1]]],
                PRIMEM["Greenwich",0,
                    ANGLEUNIT["degree",0.0174532925199433]],
                ID["EPSG",4300]],
            CONVERSION["Irish Grid",
                METHOD["Transverse Mercator",
                    ID["EPSG",9807]],
                PARAMETER["Latitude of natural origin",53.5,
                    ANGLEUNIT["degree",0.0174532925199433],
                    ID["EPSG",8801]],
                PARAMETER["Longitude of natural origin",-8,
                    ANGLEUNIT["degree",0.0174532925199433],
                    ID["EPSG",8802]],
                PARAMETER["Scale factor at natural origin",1.000035,
                    SCALEUNIT["unity",1],
                    ID["EPSG",8805]],
                PARAMETER["False easting",200000,
                    LENGTHUNIT["metre",1],
                    ID["EPSG",8806]],
                PARAMETER["False northing",250000,
                    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["Ireland - onshore. United Kingdom (UK) - Northern Ireland (Ulster) - onshore."],
                BBOX[51.39,-10.56,55.43,-5.34]],
            ID["EPSG",29903]]],
    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",482.5,
            ID["EPSG",8605]],
        PARAMETER["Y-axis translation",-130.6,
            ID["EPSG",8606]],
        PARAMETER["Z-axis translation",564.6,
            ID["EPSG",8607]],
        PARAMETER["X-axis rotation",-1.042,
            ID["EPSG",8608]],
        PARAMETER["Y-axis rotation",-0.214,
            ID["EPSG",8609]],
        PARAMETER["Z-axis rotation",-0.631,
            ID["EPSG",8610]],
        PARAMETER["Scale difference",1.00000815,
            ID["EPSG",8611]]]]

Definition: ESRI Well Known Text

PROJCS["TM75_Irish_Grid",
    GEOGCS["GCS_TM75",
        DATUM["D_TM75",
            SPHEROID["Airy_Modified",6377340.189,299.3249646]],
        PRIMEM["Greenwich",0.0],
        UNIT["Degree",0.0174532925199433]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["False_Easting",200000.0],
    PARAMETER["False_Northing",250000.0],
    PARAMETER["Central_Meridian",-8.0],
    PARAMETER["Scale_Factor",1.000035],
    PARAMETER["Latitude_Of_Origin",53.5],
    UNIT["Meter",1.0]]

Definition: PROJ.4

+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +units=m +no_defs +type=crs

Definition: JavaScript (Proj4js)

proj4.defs("EPSG:29903","+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +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": "TM75 / Irish Grid",
        "base_crs": {
            "name": "TM75",
            "datum": {
                "type": "GeodeticReferenceFrame",
                "name": "Geodetic Datum of 1965",
                "ellipsoid": {
                    "name": "Airy Modified 1849",
                    "semi_major_axis": 6377340.189,
                    "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": 4300
            }
        },
        "conversion": {
            "name": "Irish Grid",
            "method": {
                "name": "Transverse Mercator",
                "id": {
                    "authority": "EPSG",
                    "code": 9807
                }
            },
            "parameters": [
                {
                    "name": "Latitude of natural origin",
                    "value": 53.5,
                    "unit": "degree",
                    "id": {
                        "authority": "EPSG",
                        "code": 8801
                    }
                },
                {
                    "name": "Longitude of natural origin",
                    "value": -8,
                    "unit": "degree",
                    "id": {
                        "authority": "EPSG",
                        "code": 8802
                    }
                },
                {
                    "name": "Scale factor at natural origin",
                    "value": 1.000035,
                    "unit": "unity",
                    "id": {
                        "authority": "EPSG",
                        "code": 8805
                    }
                },
                {
                    "name": "False easting",
                    "value": 200000,
                    "unit": "metre",
                    "id": {
                        "authority": "EPSG",
                        "code": 8806
                    }
                },
                {
                    "name": "False northing",
                    "value": 250000,
                    "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": 29903
        }
    },
    "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": 482.5,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8605
                }
            },
            {
                "name": "Y-axis translation",
                "value": -130.6,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8606
                }
            },
            {
                "name": "Z-axis translation",
                "value": 564.6,
                "unit": "metre",
                "id": {
                    "authority": "EPSG",
                    "code": 8607
                }
            },
            {
                "name": "X-axis rotation",
                "value": -1.042,
                "unit": {
                    "type": "AngularUnit",
                    "name": "arc-second",
                    "conversion_factor": 4.84813681109536e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8608
                }
            },
            {
                "name": "Y-axis rotation",
                "value": -0.214,
                "unit": {
                    "type": "AngularUnit",
                    "name": "arc-second",
                    "conversion_factor": 4.84813681109536e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8609
                }
            },
            {
                "name": "Z-axis rotation",
                "value": -0.631,
                "unit": {
                    "type": "AngularUnit",
                    "name": "arc-second",
                    "conversion_factor": 4.84813681109536e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8610
                }
            },
            {
                "name": "Scale difference",
                "value": 8.15,
                "unit": {
                    "type": "ScaleUnit",
                    "name": "parts per million",
                    "conversion_factor": 1e-06
                },
                "id": {
                    "authority": "EPSG",
                    "code": 8611
                }
            }
        ]
    }
}

Definition: GeoServer

29903=PROJCS["TM75 / Irish Grid",GEOGCS["TM75",DATUM["Geodetic_Datum_of_1965",SPHEROID["Airy Modified 1849",6377340.189,299.3249646],TOWGS84[482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4300"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",53.5],PARAMETER["central_meridian",-8],PARAMETER["scale_factor",1.000035],PARAMETER["false_easting",200000],PARAMETER["false_northing",250000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","29903"]]

Definition: MapServer - MAPfile

PROJECTION
	"proj=tmerc"
	"lat_0=53.5"
	"lon_0=-8"
	"k=1.000035"
	"x_0=200000"
	"y_0=250000"
	"a=6377340.189"
	"rf=299.3249646"
	"towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15"
	"units=m"
	"no_defs"
	"type=crs"
END

Definition: Mapnik

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +units=m +no_defs +type=crs">
	<Layer srs="+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +units=m +no_defs +type=crs">
	</Layer>
</Map>

Definition: SQL (PostGIS)

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 29903, 'EPSG', 29903, '+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +units=m +no_defs +type=crs', 'PROJCS["TM75 / Irish Grid",GEOGCS["TM75",DATUM["Geodetic_Datum_of_1965",SPHEROID["Airy Modified 1849",6377340.189,299.3249646],TOWGS84[482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4300"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",53.5],PARAMETER["central_meridian",-8],PARAMETER["scale_factor",1.000035],PARAMETER["false_easting",200000],PARAMETER["false_northing",250000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","29903"]]');