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Convert ITRF89 to ITRF90

Convert coordinates from ITRF89 (EPSG:4911) to ITRF90 (EPSG:4912) — official EPSG transformation parameters, accuracy and area of use, with a free in-browser converter.

Direct link to this transformation: epsgtransform.com/transform/epsg-4911-to-epsg-4912

Official EPSG transformations from ITRF89 to ITRF90

The EPSG Geodetic Parameter Dataset defines 2 transformations between ITRF89 (EPSG:4911) and ITRF90 (EPSG:4912). Each applies to a specific area — pick the one whose area of use covers your data.

ITRF89 to ITRF90 (1)

EPSG:9021±0.01 mBest accuracy
Method:
Position Vector transformation (geocentric domain)
Area of use:
World
Scope:
Geodesy.
ParameterValueUnit
X-axis translation(tx)-0.5centimetre
Y-axis translation(ty)-2.4centimetre
Z-axis translation(tz)3.8centimetre
X-axis rotation(rx)0milliarc-second
Y-axis rotation(ry)0milliarc-second
Z-axis rotation(rz)0milliarc-second
Scale difference(ds)-3parts per billion

Scale difference in ppb and scale difference rate in ppb/yr where 1/billion = 1E-9 or nm/m. Superseded by parameter values derived from transformations to ITRF2020 (change in scale difference), see EPSG:10140.

ITRF89 to ITRF90 (2)

EPSG:10140±0.01 m
Method:
Position Vector transformation (geocentric domain)
Area of use:
World
Scope:
Geodesy.
ParameterValueUnit
X-axis translation(tx)-0.5centimetre
Y-axis translation(ty)-2.4centimetre
Z-axis translation(tz)3.8centimetre
X-axis rotation(rx)0milliarc-second
Y-axis rotation(ry)0milliarc-second
Z-axis rotation(rz)0milliarc-second
Scale difference(ds)-3.4parts per billion

Parameter values derived from differences in CTs to ITRF2020 (codes 10103 and 10104). These supersede all values published in past IERS/ITRF documentation (CT code 9021). Scale difference in ppb and scale difference rate in ppb/yr where 1/billion = 1E-9.

Convert EPSG:4911 to EPSG:4912 in code

The same transformation with common GIS tools and libraries:

from pyproj import Transformer

transformer = Transformer.from_crs("EPSG:4911", "EPSG:4912", always_xy=True)
x, y = transformer.transform(-73.9857, 40.7484)
print(x, y)

Source: EPSG:4911ITRF89

geocentric Cartesian system (Earth-centred Earth-fixed) · Area of use: World

+proj=geocent +ellps=GRS80 +units=m +no_defs +type=crs
More about EPSG:4911

Target: EPSG:4912ITRF90

geocentric Cartesian system (Earth-centred Earth-fixed) · Area of use: World

+proj=geocent +ellps=GRS80 +units=m +no_defs +type=crs
More about EPSG:4912

Frequently asked questions

How accurate is converting ITRF89 to ITRF90?
The most accurate official EPSG transformation between these systems is accurate to about ±0.01 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:4912 to EPSG:4911