EPSG systems

EPSG:3942 RGF93 v1 / CC42

Projected system (Lambert Conic Conformal (2SP)) in use: France - mainland south of 43°N and Corsica. The full definition below, and conversion in one click.

System record
CodeEPSG:3942
NameRGF93 v1 / CC42
TypeProjected system — Lambert Conic Conformal (2SP)
Area of use France - mainland south of 43°N and Corsica
France onshore - mainland south of 43°N and Corsica.
Bounds W -1,06° · S 41,31° · E 9,63° · N 43,07°
Countries France
DatumReseau Geodesique Francais 1993 v1
Ellipsoid GRS 1980 a = 6378137 m · 1/f = 298.257222101
Base geographic system EPSG:4171 — RGF93 v1
Unit metre (X east, Y north)
Transformation to WGS 84 RGF93 v1 to WGS 84 (1) (EPSG:1671) — accuracy 1 m
ScopeCadastre, engineering survey.
In CarteBuilt-in grid (code FCC42), with the reference cities of the guide.

Projection parameters

ParameterValueUnit
Latitude of false origin42degree
Longitude of false origin3degree
Latitude of 1st standard parallel41.25degree
Latitude of 2nd standard parallel42.75degree
Easting at false origin1700000metre
Northing at false origin1200000metre

proj4 definition

+proj=lcc +lat_1=41.25 +lat_2=42.75 +lat_0=42 +lon_0=3 +x_0=1700000 +y_0=1200000 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

Paste it into QGIS, proj4js, PostGIS (spatial_ref_sys) or GDAL. +towgs84 carries the EPSG transformation to WGS 84; the official code stays EPSG:3942.

WKT (ESRI format, the .prj content)

PROJCS["RGF_1993_CC42",GEOGCS["GCS_RGF_1993",DATUM["D_RGF_1993",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Lambert_Conformal_Conic"],PARAMETER["False_Easting",1700000.0],PARAMETER["False_Northing",1200000.0],PARAMETER["Central_Meridian",3.0],PARAMETER["Standard_Parallel_1",41.25],PARAMETER["Standard_Parallel_2",42.75],PARAMETER["Latitude_Of_Origin",42.0],UNIT["Meter",1.0]]

All systems — France

Source: EPSG registry v11.022 (IOGP), through the PROJ database. Always check a code on epsg.org before contractual work.