Coordinate Systems
EPSG:4326 (WGS 84 Latitude/Longitude)
Summary
EPSG:4326 is the WGS 84 geographic coordinate reference system with coordinates in decimal degrees. The EPSG definition orders axes latitude then longitude, but many formats (GeoJSON, KML, Shapefile .prj usage, PROJ “traditional GIS order”) store longitude first. It is used for data exchange and GPS output, not for measuring distances or areas, which need a projected CRS such as UTM.
Definition
EPSG:4326: the geographic 2D coordinate reference system of the WGS 84 datum ensemble, axes latitude (north) and longitude (east) in degrees.
- Datum: WGS 84 ensemble
- Units: degrees
- EPSG axis order: lat, lon
- GeoJSON order: lon, lat
- OGC CRS84 = lon, lat
Definition
| Property | Value |
|---|---|
| Type | Geographic 2D |
| Datum | World Geodetic System 1984 ensemble |
| Ellipsoid | WGS 84 (a = 6 378 137 m, 1/f = 298.257223563) |
| Prime meridian | Greenwich |
| Axes | Geodetic latitude (N), geodetic longitude (E) |
| Units | degree |
| Area of use | World |
Axis order
Officially EPSG:4326 is latitude, longitude. GeoJSON (RFC 7946), KML and most web maps use longitude, latitude, which corresponds to OGC:CRS84. WMS 1.3 and WFS 2.0 honour the EPSG order, which is why the same request can return swapped coordinates in different software. GeoCAD Bridge labels each input explicitly. See axis order.
EPSG:4326 versus EPSG:3857
EPSG:3857 is a projected CRS in metres used for web map tiles. Data are often stored in 4326 and displayed in 3857. Neither is suitable for engineering measurement: use UTM or a national grid.
Worked example
Riyadh in EPSG:4326: latitude 24.7136°, longitude 46.6753° (or 24°42′49″ N, 46°40′31″ E). In GeoJSON this is written [46.6753, 24.7136]. In EPSG:32638 (UTM 38N) it is E 669,459.6, N 2,734,271.7.
FAQ
Is EPSG:4326 in metres?
No, it is in degrees. One degree of latitude is about 111 km; one degree of longitude is about 111 km × cos(latitude).
Why are my points in the ocean off Africa?
Probably latitude and longitude are swapped, or both are zero (the “null island” at 0°, 0°).
Should I store data in EPSG:4326?
It is fine for exchange and web use. For survey and engineering data keep the native projected CRS and record it in the metadata.
Related tools and articles
Tools
- Coordinate TransformationConvert between EPSG coordinate systems.
- Lat/Long to UTMConvert geographic coordinates to UTM.
- EPSG LibraryLook up EPSG codes and parameters.
Articles
- WGS 84: World Geodetic System 1984WGS 84 is the global geodetic reference system used by GPS. It defines an ellipsoid (a = 6 378 137 m, 1/f = 29…
- Axis Order: Latitude/Longitude vs Longitude/LatitudeAxis order is the sequence in which coordinate values are written. EPSG defines EPSG:4326 as latitude then lon…
- EPSG:3857 Web Mercator (Pseudo-Mercator)EPSG:3857 (WGS 84 / Pseudo-Mercator) is the projection used by web map tiles from Google, Bing, OpenStreetMap …
- UTM Coordinate System ExplainedUTM divides the world between 80°S and 84°N into 60 zones, each 6° of longitude wide and projected with a Tran…
- Geographic CRSReference topic
References
- IOGP. EPSG Geodetic Parameter Dataset, epsg.org.
- IETF. RFC 7946 The GeoJSON Format, 2016.
- ISO 19111:2019 Geographic information — Referencing by coordinates.
Cite this page
GeoCAD Bridge. “EPSG:4326 (WGS 84 Latitude/Longitude).” GeoCAD Bridge Knowledge Center, updated 2026-10-05. https://www.geocadbridge.com/knowledge/coordinate-systems-epsg-4326/