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Convert GDA94 to GDA94 + AHD height

Convert coordinates from GDA94 (EPSG:4939) to GDA94 + AHD height (EPSG:9464) — official EPSG transformation parameters, accuracy and area of use, with a free in-browser converter.

Direct link to this transformation: epsgtransform.com/transform/epsg-4939-to-epsg-9464

Official EPSG transformation from GDA94 to GDA94 + AHD height

The EPSG Geodetic Parameter Dataset defines 1 transformation between GDA94 (EPSG:4939) and GDA94 + AHD height (EPSG:9464). Its parameters, accuracy and area of use are listed below.

GDA94 to GDA94 + AHD height (1)

EPSG:9467±0.15 m
Method:
Geog3D to Geog2D+GravityRelatedHeight (AUSGeoidv2)
Area of use:
Australia - onshore
Scope:
Derivation of gravity-related heights from GNSS observations.

Grid file: AUSGeoid09_V1.01.gsb

Reversible alternative to GDA94 to AHD height (1) and GDA94 to AHD (Tasmania) height (2) (codes 5656 and 5657). Uses AUSGeoid09 model which uses bi-cubic interpolation; bi-linear interpolation will give results agreeing to within 1cm 99.97% of the time.

Convert EPSG:4939 to EPSG:9464 in code

The same transformation with common GIS tools and libraries:

from pyproj import Transformer

transformer = Transformer.from_crs("EPSG:4939", "EPSG:9464", always_xy=True)
x, y = transformer.transform(-73.9857, 40.7484)
print(x, y)

Source: EPSG:4939 — GDA94

geographic system using latitude, longitude and ellipsoidal height · Area of use: Australia - GDA

+proj=longlat +ellps=GRS80 +no_defs +type=crs
More about EPSG:4939 →

Target: EPSG:9464 — GDA94 + AHD height

compound horizontal + vertical reference system · Area of use: Australia Christmas and Cocos - onshore

+proj=longlat +ellps=GRS80 +geoidgrids=au_ga_AUSGeoid2020_20180201.tif +geoid_crs=WGS84 +vunits=m +no_defs +type=crs
More about EPSG:9464 →

Frequently asked questions

How accurate is converting GDA94 to GDA94 + AHD height?
The most accurate official EPSG transformation between these systems is accurate to about ±0.15 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:9464 to EPSG:4939 →