EPSG Library · North Africa

EPSG:26191 — Merchich / Nord Maroc

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

Summary

EPSG:26191 (Merchich / Nord Maroc) is a projected coordinate reference system on the Merchich datum using the Lambert Conic Conformal (1SP) method, with coordinates in metres. Area of use: Morocco onshore north of 35 grads North (31°30'N).

Type: projected
Datum: Merchich
Units: metre
Axes: X, Y

Definition

EPSG:26191 as published in the EPSG Dataset (PROJ 9.5.1).
Property	Value
EPSG code	EPSG:26191
Name	Merchich / Nord Maroc
Type	Projected CRS
Datum	Merchich
Ellipsoid	Clarke 1880 (IGN) (a = 6,378,249.200 m, 1/f = 293.466021)
Prime meridian	Greenwich
Projection method	Lambert Conic Conformal (1SP)
Axes	Easting (X, east, metre); Northing (Y, north, metre)
Scope	Engineering survey, topographic mapping.
Bounding box	-9.85° to -1.01° longitude, 31.49° to 35.97° latitude

Area of use

Morocco onshore north of 35 grads North (31°30'N).

Projection parameters

Lambert Conic Conformal (1SP) parameters.
Parameter	Value	Unit
Latitude of natural origin	37	grad
Longitude of natural origin	-6	grad
Scale factor at natural origin	0.999625769	unity
False easting	500,000	metre
False northing	300,000	metre

Example coordinates

A WGS 84 point at longitude -5.43°, latitude 33.73° (inside the area of use) has these coordinates in EPSG:26191:

Computed with PROJ using the EPSG default operation: axis order change (2D) + Inverse of Merchich to WGS 84 (1) + Nord Maroc.
Axis	Value	Unit
X	497,072.441	m
Y	347,966.572	m

At this point the projection scale factor is 0.99965383 and the grid convergence is -0.016471°.

Open this conversion in the coordinate converter

Transformations to WGS 84

Candidate operations from the EPSG Dataset, best first as ranked by PROJ.
Operation	Accuracy	Area of use
axis order change (2D) + Merchich to WGS 84 (1) + axis order change (2D)	7 m	Morocco - onshore.

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=lcc +lat_1=33.3 +lat_0=33.3 +lon_0=-5.4 +k_0=0.999625769 +x_0=500000 +y_0=300000 +ellps=clrk80ign +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.

Proj4js definition used by the converter

+proj=lcc +lat_1=33.3 +lat_0=33.3 +lon_0=-5.4 +k_0=0.999625769 +x_0=500000 +y_0=300000 +ellps=clrk80ign +units=m +towgs84=31,146,47 +no_defs

Datum shift from Merchich to WGS 84 (1) (EPSG accuracy 7 m), the best single Helmert operation for this area of use. Where PROJ prefers a grid-based or multi-step operation (see the table above), results can differ by up to that operation's accuracy.

WKT2:2019

PROJCRS["Merchich / Nord Maroc", BASEGEOGCRS["Merchich", DATUM["Merchich", ELLIPSOID["Clarke 1880 (IGN)",6378249.2,293.466021293627, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4261]], CONVERSION["Nord Maroc", METHOD["Lambert Conic Conformal (1SP)", ID["EPSG",9801]], PARAMETER["Latitude of natural origin",37, ANGLEUNIT["grad",0.0157079632679489], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-6, ANGLEUNIT["grad",0.0157079632679489], ID["EPSG",8802]], PARAMETER["Scale factor at natural origin",0.999625769, SCALEUNIT["unity",1], ID["EPSG",8805]], PARAMETER["False easting",500000, LENGTHUNIT["metre",1], ID["EPSG",8806]], PARAMETER["False northing",300000, LENGTHUNIT["metre",1], ID["EPSG",8807]]], CS[Cartesian,2], AXIS["easting (X)",east, ORDER[1], LENGTHUNIT["metre",1]], AXIS["northing (Y)",north, ORDER[2], LENGTHUNIT["metre",1]], USAGE[ SCOPE["Engineering survey, topographic mapping."], AREA["Morocco onshore north of 35 grads North (31°30'N)."], BBOX[31.49,-9.85,35.97,-1.01]], ID["EPSG",26191]]

Downloads

26191.prj — ESRI WKT for shapefiles
26191.wkt — OGC WKT2:2019

FAQ

What is EPSG:26191?

Where can EPSG:26191 be used?

Its area of use is: Morocco onshore north of 35 grads North (31°30'N).

Is EPSG:26191 in metres or degrees?

EPSG:26191 is projected, so coordinates are easting and northing in metres, not degrees.

How do I convert EPSG:26191 to latitude and longitude?

Transform from EPSG:26191 to EPSG:4326 (WGS 84). In GeoCAD Bridge open the coordinate converter with EPSG:26191 preselected, enter easting and northing, and choose WGS 84 as the target.

How accurate is the transformation from EPSG:26191 to WGS 84?

The most accurate EPSG transformation listed here is “axis order change (2D) + Merchich to WGS 84 (1) + axis order change (2D)”, with a stated accuracy of 7 m for Morocco - onshore.. Always check the area of use before applying it.

Coordinate systems

Articles

Tools

References

IOGP. EPSG Geodetic Parameter Dataset, epsg.org/crs_26191.
PROJ 9.5.1 / pyproj 3.7.2, used to compute every value on this page.

Cite this page

GeoCAD Bridge. “EPSG:26191 — Merchich / Nord Maroc.” GeoCAD Bridge EPSG Library, updated 2026-10-05. https://www.geocadbridge.com/epsg/26191/