EPSG Library · Saudi Arabia

EPSG:9331 — KSA-GRF17

Source: EPSG Dataset via PROJ 9.5.1 · Updated 2026-10-05

Summary

EPSG:9331 (KSA-GRF17) is an Earth-centred, Earth-fixed geocentric CRS on the Kingdom of Saudi Arabia Geodetic Reference Frame 2017 datum with X, Y, Z coordinates in metres. Area of use: Saudi Arabia - onshore and offshore.

Type: geocentric
Datum: Kingdom of Saudi Arabia Geodetic Reference Frame 2017
Units: metre
Axes: X, Y, Z

Definition

EPSG:9331 as published in the EPSG Dataset (PROJ 9.5.1).
Property	Value
EPSG code	EPSG:9331
Name	KSA-GRF17
Type	Geocentric CRS
Datum	Kingdom of Saudi Arabia Geodetic Reference Frame 2017
Ellipsoid	GRS 1980 (a = 6,378,137.000 m, 1/f = 298.257222)
Prime meridian	Greenwich
Axes	Geocentric X (X, geocentricX, metre); Geocentric Y (Y, geocentricY, metre); Geocentric Z (Z, geocentricZ, metre)
Scope	Geodesy, cadastre, engineering survey, topographic mapping.
Bounding box	34.44° to 55.67° longitude, 16.29° to 32.16° latitude

Area of use

Saudi Arabia - onshore and offshore.

Example coordinates

A WGS 84 point at longitude 45.055°, latitude 24.225° (inside the area of use) has these coordinates in EPSG:9331:

Computed with PROJ using the EPSG default operation.
Axis	Value	Unit
X	4,111,243.812	m
Y	4,119,144.734	m
Z	2,601,030.079	m

Transformations to WGS 84

Candidate operations from the EPSG Dataset, best first as ranked by PROJ.
Operation	Accuracy	Area of use
Conversion from KSA-GRF17 (geocentric) to KSA-GRF17 (geog2D) + KSA-GRF17 to WGS 84 (1) + axis order change (2D)	1 m	Saudi Arabia - onshore and offshore.

Transformations change the datum, so each has an accuracy and an area of use. Choose the most accurate one that covers your data and record its name. See datum transformations.

Definitions and downloads

PROJ string

+proj=geocent +ellps=GRS80 +units=m +no_defs +type=crs

A PROJ string cannot carry every EPSG detail (axis order, datum ensemble, transformations). Prefer WKT2 or the EPSG code itself.

WKT2:2019

GEODCRS["KSA-GRF17", DATUM["Kingdom of Saudi Arabia Geodetic Reference Frame 2017", ELLIPSOID["GRS 1980",6378137,298.257222101, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], CS[Cartesian,3], AXIS["(X)",geocentricX, ORDER[1], LENGTHUNIT["metre",1]], AXIS["(Y)",geocentricY, ORDER[2], LENGTHUNIT["metre",1]], AXIS["(Z)",geocentricZ, ORDER[3], LENGTHUNIT["metre",1]], USAGE[ SCOPE["Geodesy, cadastre, engineering survey, topographic mapping."], AREA["Saudi Arabia - onshore and offshore."], BBOX[16.29,34.44,32.16,55.67]], ID["EPSG",9331]]

Downloads

9331.wkt — OGC WKT2:2019

FAQ

What is EPSG:9331?

Where can EPSG:9331 be used?

Its area of use is: Saudi Arabia - onshore and offshore.

What is the axis order of EPSG:9331?

By the EPSG definition: Geocentric X, Geocentric Y, Geocentric Z. Many GIS formats such as GeoJSON and KML store longitude first instead.

How accurate is the transformation from EPSG:9331 to WGS 84?

The most accurate EPSG transformation listed here is “Conversion from KSA-GRF17 (geocentric) to KSA-GRF17 (geog2D) + KSA-GRF17 to WGS 84 (1) + axis order change (2D)”, with a stated accuracy of 1 m for Saudi Arabia - onshore and offshore.. Always check the area of use before applying it.

Coordinate systems

Articles

Tools

References

IOGP. EPSG Geodetic Parameter Dataset, epsg.org/crs_9331.
PROJ 9.5.1 / pyproj 3.7.2, used to compute every value on this page.

Cite this page

GeoCAD Bridge. “EPSG:9331 — KSA-GRF17.” GeoCAD Bridge EPSG Library, updated 2026-10-05. https://www.geocadbridge.com/epsg/9331/