EPSG.dev

British National Grid - EPSG:27700

Detailed Extent

WKT

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]]

WKT2

PROJCRS["British_National_Grid", 
	BASEGEOGCRS["GCS_OSGB_1936", 
		DATUM["D_OSGB_1936", 
			ELLIPSOID["Airy_1830", 6377563.396, 299.3249646]], 
		PRIMEM["Greenwich", 0.0], 
		CS[ellipsoidal, 2], 
		AXIS["Latitude (lat)", north, 
			ORDER[1]], 
		AXIS["Longitude (lon)", east, 
			ORDER[2]], 
		ANGLEUNIT["Degree", 0.0174532925199433]], 
	CONVERSION["Transverse_Mercator", 
		METHOD["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]], 
	CS[Cartesian, 2], 
	AXIS["Easting (X)", east, 
		ORDER[1]], 
	AXIS["Northing (Y)", north, 
		ORDER[2]], 
	LENGTHUNIT["Meter", 1.0], 
	ID["EPSG", "27700"]]

Data from @esri/proj-codes

{
  "wkid": 27700,
  "latestWkid": 27700,
  "gcsWkid": 4277,
  "macro": "PE_PCS_OSGB_1936_BRITISH_GRID",
  "name": "British_National_Grid",
  "wkt": "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]]",
  "wkt2": "PROJCRS[\"British_National_Grid\",BASEGEOGCRS[\"GCS_OSGB_1936\",DATUM[\"D_OSGB_1936\",ELLIPSOID[\"Airy_1830\",6377563.396,299.3249646]],PRIMEM[\"Greenwich\",0.0],CS[ellipsoidal,2],AXIS[\"Latitude (lat)\",north,ORDER[1]],AXIS[\"Longitude (lon)\",east,ORDER[2]],ANGLEUNIT[\"Degree\",0.0174532925199433]],CONVERSION[\"Transverse_Mercator\",METHOD[\"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]],CS[Cartesian,2],AXIS[\"Easting (X)\",east,ORDER[1]],AXIS[\"Northing (Y)\",north,ORDER[2]],LENGTHUNIT[\"Meter\",1.0],ID[\"EPSG\",\"27700\"]]",
  "description": "British National Grid",
  "authority": "EPSG",
  "version": "6.3(3.0.1)",
  "deprecated": "no",
  "areaname": "UK - Britain and UKCS 49~45'N to 61~N, 9~W to 2~E",
  "extent": {
    "slat": 49.75,
    "nlat": 61.01,
    "llon": -9.01,
    "rlon": 2.01
  }
}