Convert Fort Marigot to RGAF09

Convert coordinates from Fort Marigot (EPSG:4621) to RGAF09 (EPSG:5489) — 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-4621-to-epsg-5489

Official EPSG transformation from Fort Marigot to RGAF09

The EPSG Geodetic Parameter Dataset defines 1 transformation between Fort Marigot (EPSG:4621) and RGAF09 (EPSG:5489). Its parameters, accuracy and area of use are listed below.

Fort Marigot to RGAF09 (1)

EPSG:5493±10 m

Method:: Position Vector transformation (geog2D domain)
Area of use:: Guadeloupe - St Martin and St Barthelemy - onshore
Scope:: Transformation of coordinates at 10m level of accuracy.

Parameter	Value	Unit
X-axis translation(tx)	151.613	metre
Y-axis translation(ty)	253.832	metre
Z-axis translation(tz)	-429.084	metre
X-axis rotation(rx)	-0.0506	arc-second
Y-axis rotation(ry)	0.0958	arc-second
Z-axis rotation(rz)	-0.5974	arc-second
Scale difference(ds)	-0.3971	parts per million

Convert EPSG:4621 to EPSG:5489 in code

The same transformation with common GIS tools and libraries:

from pyproj import Transformer

transformer = Transformer.from_crs("EPSG:4621", "EPSG:5489", always_xy=True)
x, y = transformer.transform(-73.9857, 40.7484)
print(x, y)

Source: EPSG:4621 — Fort Marigot

geographic system using latitude and longitude on an ellipsoid · Area of use: Guadeloupe - St Martin and St Barthelemy - onshore

+proj=longlat +ellps=intl +towgs84=137,248,-430,0,0,0,0 +no_defs +type=crs

More about EPSG:4621 →

Target: EPSG:5489 — RGAF09

geographic system using latitude and longitude on an ellipsoid · Area of use: Caribbean - French Antilles

+proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs +type=crs

More about EPSG:5489 →

Frequently asked questions

How accurate is converting Fort Marigot to RGAF09?: The most accurate official EPSG transformation between these systems is accurate to about ±10 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:5489 to EPSG:4621 →