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Convert ETRS89 to MRH21-IRF

Convert coordinates from ETRS89 (EPSG:4258) to MRH21-IRF (EPSG:9866) — official EPSG transformation parameters, accuracy and area of use, with a free in-browser converter.

Direct link to this transformation: epsgtransform.com/transform/epsg-4258-to-epsg-9866

Official EPSG transformation from ETRS89 to MRH21-IRF

The EPSG Geodetic Parameter Dataset defines 1 transformation between ETRS89 (EPSG:4258) and MRH21-IRF (EPSG:9866). Its parameters, accuracy and area of use are listed below.

ETRS89 to MRH21-IRF (1)

EPSG:9867±0 m
Method:
NTv2
Area of use:
UK - Cardiff to Lincoln
Scope:
Engineering survey and topographic mapping for railway applications.

Grid file: TN15-ETRS89-to-MRH21-IRF.gsb

In conjunction with MRH21-TM map projection (code 9868) applied to MRH21-IRF (code 9866), emulates the MRH21 Snake projection. Applied to ETRS89 (as realized through the OSNet v2009) defines MRH21-IRF hence is errorless.

Convert EPSG:4258 to EPSG:9866 in code

The same transformation with common GIS tools and libraries:

from pyproj import Transformer

transformer = Transformer.from_crs("EPSG:4258", "EPSG:9866", always_xy=True)
x, y = transformer.transform(-73.9857, 40.7484)
print(x, y)

Source: EPSG:4258 — ETRS89

geographic system using latitude and longitude on an ellipsoid · Area of use: Europe - ETRF by country

+proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs +type=crs
More about EPSG:4258 →

Target: EPSG:9866 — MRH21-IRF

geographic system using latitude and longitude on an ellipsoid · Area of use: UK - Cardiff to Lincoln

+proj=longlat +ellps=GRS80 +no_defs +type=crs
More about EPSG:9866 →

Frequently asked questions

How accurate is converting ETRS89 to MRH21-IRF?
The most accurate official EPSG transformation between these systems is accurate to about ±0 m within its stated area of use. Browser-based converters approximate datum shifts with Helmert parameters; for surveying-grade work apply the official transformation (including the grid-shift files listed below) in a desktop GIS.
Does my data leave the browser when I use this converter?
No. All coordinate transformations are computed locally in your browser using proj4js. The coordinates you enter are never transmitted to any server.
Need the reverse? Convert EPSG:9866 to EPSG:4258 →