EPSG:29903

TM75 / Irish Grid

Available transformations
to EPSG:4258
EPSG:4258 - ETRS89

Selected transformation

Method: General polynomial of degree 6

Remarks: Derived at 183 points, accuracy 0.4m (95%). Use iteration for reverse transformation ETRS89 to TM75. Emulated by NTv2 method (code 6946) and used as approximate CT to WGS 84 (code 1042).

Information source: Ordnance Survey of Great Britain, http://www.gps.gov.uk

Revision date: 2020-03-14

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.
MapTiler banner

Definition: OGC Well Known Text

PROJCS["TM75 / Irish Grid",
    GEOGCS["TM75",
        DATUM["Geodetic_Datum_of_1965",
            SPHEROID["Airy Modified 1849",6377340.189,299.3249646,
                AUTHORITY["EPSG","7002"]],
            AUTHORITY["EPSG","6300"]],
        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)

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]]

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 +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 +units=m +no_defs +type=crs");

Definition: JSON

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "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"
            }
        ]
    },
    "scope": "Engineering survey, topographic mapping.",
    "area": "Ireland - onshore. United Kingdom (UK) - Northern Ireland (Ulster) - onshore.",
    "bbox": {
        "south_latitude": 51.39,
        "west_longitude": -10.56,
        "north_latitude": 55.43,
        "east_longitude": -5.34
    },
    "id": {
        "authority": "EPSG",
        "code": 29903
    }
}

Definition: GeoServer

29903=PROJCS["TM75 / Irish Grid",GEOGCS["TM75",DATUM["Geodetic_Datum_of_1965",SPHEROID["Airy Modified 1849",6377340.189,299.3249646,AUTHORITY["EPSG","7002"]],AUTHORITY["EPSG","6300"]],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"
	"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 +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 +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 +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,AUTHORITY["EPSG","7002"]],AUTHORITY["EPSG","6300"]],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"]]');