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EPSG:7844 — GDA2020

GDA2020 — Australia's current geodetic datum, replacing GDA94 to track the continent's 7 cm/year northwards drift.

Code
EPSG:7844
Type
Geographic 2D
Area
Australia - GDA

PROJ definition

+proj=longlat +ellps=GRS80 +no_defs +type=crs

Geographic bounds

W 93.41°   S -60.55°   E 173.34°   N -8.47°

Convert coordinates with EPSG:7844

Official EPSG transformations for GDA2020

Datum transformations involving EPSG:7844 published in the EPSG dataset, with parameters, accuracy and area of use:

About EPSG:7844

EPSG:7844 is the Geocentric Datum of Australia 2020 (GDA2020), aligned with ITRF2014 at epoch 2020.00. It replaced GDA94 (EPSG:4283) as Australia's official datum on 1 January 2020 because the Australian plate has drifted ~1.8 m north-east since GDA94 was fixed in 1994 — a difference too large to ignore for surveying or modern GNSS workflows.

The matching projected CRSs are MGA2020 zones 46 to 59 (EPSG:7846-7859), Lambert conformal conic GDA2020 (EPSG:7845), and Australian Albers GDA2020 (EPSG:9473). All federal mapping is required to be in GDA2020 by 2030; state cadastral migrations are well advanced. Conversion between GDA94 and GDA2020 is a published Helmert transformation (EPSG:8048) accurate to a few millimetres.

Common use cases

  • All current Geoscience Australia federal mapping
  • GNSS surveying and CORS-derived positioning
  • State cadastre and infrastructure (post 2020)
  • Cross-jurisdictional spatial data exchange

Common transformations from EPSG:7844

Frequently asked questions

Should I use GDA2020 or GDA94?
Use GDA2020 (EPSG:7844) for any new work. Existing data tagged GDA94 (EPSG:4283) needs to be transformed using EPSG:8048 — the differences are ~1.8 m, too large to ignore.
What is the proj4 string for EPSG:7844?
The proj4 definition for EPSG:7844 is: +proj=longlat +ellps=GRS80 +no_defs +type=crs
Where is EPSG:7844 used?
EPSG:7844 (GDA2020) is defined for the area: Australia - GDA.