Convert OSNI 1952 to WGS 84

Convert coordinates from OSNI 1952 (EPSG:4188) to WGS 84 (EPSG:4326) — official EPSG transformation parameters, accuracy and area of use, with a free in-browser converter.

From

Input (lon, lat (decimal degrees))

Output (lon, lat (decimal degrees))

Direct link to this transformation: epsgtransform.com/transform/epsg-4188-to-epsg-4326

Official EPSG transformation from OSNI 1952 to WGS 84

The EPSG Geodetic Parameter Dataset defines 1 transformation between OSNI 1952 (EPSG:4188) and WGS 84 (EPSG:4326). Its parameters, accuracy and area of use are listed below.

OSNI 1952 to WGS 84 (1)

EPSG:1955±1 m

Method:: Position Vector transformation (geog2D domain)
Area of use:: UK - Northern Ireland - onshore
Scope:: (null/copy) Approximation for medium and low accuracy applications assuming equality between plate-fixed static and earth-fixed dynamic CRSs, ignoring static/dynamic CRS differences.

Parameter	Value	Unit
X-axis translation(tx)	482.5	metre
Y-axis translation(ty)	-130.6	metre
Z-axis translation(tz)	564.6	metre
X-axis rotation(rx)	-1.042	arc-second
Y-axis rotation(ry)	-0.214	arc-second
Z-axis rotation(rz)	-0.631	arc-second
Scale difference(ds)	8.15	parts per million

Parameter values from TM75 to ETRS89 (2) (code 1953). Assumes each pair of (i) OSNI 1952 and TM75, and (ii) ETRS89 and WGS 84, can be considered the same to within the accuracy of the transformation.

Convert EPSG:4188 to EPSG:4326 in code

The same transformation with common GIS tools and libraries:

from pyproj import Transformer

transformer = Transformer.from_crs("EPSG:4188", "EPSG:4326", always_xy=True)
x, y = transformer.transform(-73.9857, 40.7484)
print(x, y)

Source: EPSG:4188 — OSNI 1952

geographic system using latitude and longitude on an ellipsoid · Area of use: UK - Northern Ireland - onshore

+proj=longlat +ellps=airy +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +no_defs +type=crs

More about EPSG:4188 →

Target: EPSG:4326 — WGS 84

geographic system using latitude and longitude on an ellipsoid · Area of use: World (by country)

+proj=longlat +datum=WGS84 +no_defs +type=crs

More about EPSG:4326 →

Frequently asked questions

How accurate is converting OSNI 1952 to WGS 84?: The most accurate official EPSG transformation between these systems is accurate to about ±1 m within its stated area of use. Browser-based converters approximate datum shifts with Helmert parameters; for surveying-grade work apply the official transformation 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:4326 to EPSG:4188 →