WGS84 (G1674) (World Geodetic System 1984)
Apr 14,2026

GISBox is a one-stop 3D GIS data editing, conversion and publishing platform that supports editing in multiple GIS formats such as OSGB/GEOTIFF/RVT, converting to 3DTiles/Terrain and publishing.

Introduction

WGS84 (G1674) is one of the updated realizations of the globally used World Geodetic System 1984 (WGS84), a frame that has been improved in accuracy based on GNSS observation data. The EPSG code EPSG:4979 defines a three-dimensional geographic coordinate system that represents a position using three components: latitude, longitude, and ellipsoidal height. WGS84 (G1674) is primarily used in global navigation satellite systems and is widely employed as the positioning reference, especially for GPS. Based on an Earth-Centered, Earth-Fixed (ECEF) framework and using an Earth ellipsoid model, it enables highly accurate representation of positions on the Earth's surface.

Coordinate System Composition

The WGS84 (G1674) coordinate system consists of the following main components:

Reference Ellipsoid
WGS84 defines an ellipsoid model to approximate the shape of the Earth. The principal parameters are:

Semi-major axis: 6378137.0 m
Flattening: 1 / 298.257223563

Coordinate Components
EPSG:4979 represents a position using the following three components as a three-dimensional geographic coordinate:

Latitude
Longitude
Ellipsoidal height

Earth-Centered, Earth-Fixed (ECEF)
The system is based on an Earth-centered orthogonal coordinate system, allowing positions on Earth to also be represented as X, Y, Z three-dimensional coordinates.

Alignment with GNSS Reference Frames
WGS84 (G1674) is aligned with the International Terrestrial Reference Frame (ITRF) to maintain compatibility with international geodetic standards.

Pros

Globally unified coordinate reference: WGS84 is a geodetic datum used consistently worldwide, facilitating the sharing of position information across different countries and systems.
High compatibility with GNSS: As the standard coordinate system for GPS and other satellite positioning systems, positioning data can be used directly.
Three-dimensional positioning capability: Because EPSG:4979 is a three-dimensional coordinate system that includes height information, it can be used in fields where height is critical, such as aviation, space, and terrain analysis.
High-accuracy Earth model: By employing an Earth ellipsoid model, relatively high-accuracy position representation is possible even at the global scale.
Broad GIS compatibility: The system is natively supported as a standard in many GIS software platforms (e.g., ArcGIS and QGIS).

Cons

Not a projected coordinate system: WGS84 (EPSG:4979) is a geographic coordinate system, not a planar coordinate system, and is therefore not directly suitable for distance or area calculations. In many cases, it must be transformed to a projected coordinate system such as UTM.
Ellipsoidal height definition: Heights are expressed relative to the ellipsoid, not mean sea level, which can result in differences from actual topographic elevations.
Possible accuracy discrepancies in local surveying: Compared to local geodetic datums used in national surveys, differences of several meters may occur in localized measurements.
Requires accommodation of crustal deformation: Because surface positions change over time due to tectonic motion, long-term high-accuracy surveying requires the use of updated reference frames.

Application Scenario

WGS84 (G1674) is used as a global location infrastructure across a wide range of fields. It is adopted as the standard coordinate system in GPS navigation, smartphone location services, air navigation, marine positioning, and more. In 3D GIS, digital twins, and city modeling, EPSG:4979—which includes height information—plays an important role. Furthermore, it is used for integrating remote sensing data and global geographic data, functioning as a foundation for ensuring data compatibility across different regions and systems.