EPSG systems

EPSG:2370 Xian 1980 / 3-degree Gauss-Kruger CM 75E

Projected system (Transverse Mercator) in use: China - west of 76.5°E. The full definition below, and conversion in one click.

EPSG publishes no simple transformation to WGS 84 for this datum: conversion works on the ellipsoid alone and can be off by tens of metres.

System record
CodeEPSG:2370
NameXian 1980 / 3-degree Gauss-Kruger CM 75E
TypeProjected system — Transverse Mercator
Area of use China - west of 76.5°E
China - west of 76°30'E.
Bounds W 73,62° · S 35,81° · E 76,50° · N 40,65°
Countries China
DatumXian 1980
Ellipsoid IAG 1975 a = 6378140 m · 1/f = 298.257
Base geographic system EPSG:4610 — Xian 1980
Unit metre (X north, Y east)
Transformation to WGS 84 No simple transformation published (ellipsoid alone)
ScopeCadastre, engineering survey, topographic mapping (large scale).

Projection parameters

ParameterValueUnit
Latitude of natural origin0degree
Longitude of natural origin75degree
Scale factor at natural origin1unity
False easting500000metre
False northing0metre

proj4 definition

+proj=tmerc +lat_0=0 +lon_0=75 +k=1 +x_0=500000 +y_0=0 +ellps=IAU76 +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:2370.

WKT (ESRI format, the .prj content)

PROJCS["Xian_1980_3_Degree_GK_CM_75E",GEOGCS["GCS_Xian_1980",DATUM["D_Xian_1980",SPHEROID["Xian_1980",6378140.0,298.257]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Gauss_Kruger"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",75.0],PARAMETER["Scale_Factor",1.0],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]]

All systems — China

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