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    EPSG reference

    EPSG:4261 — Merchich

    Merchich (EPSG:4261) — a Geographic (degrees) system on the clrk80ign datum, used in Morocco. Parameters, proj4, WKT, accuracy ±0.1 m, plus a free converter to WGS84 and…

    At a glance

    EPSG
    4261
    Name
    Merchich
    Kind
    Geographic (degrees)
    Family
    Geographic (longitude/latitude)
    Ellipsoid
    clrk80ign
    Accuracy
    ±0.1 m (vs PROJ)
    Countries
    Morocco

    Area of use

    West-17.16°
    South20.71°
    East-1.01°
    North35.97°

    Projection parameters

    Projectionlonglat
    Ellipsoidclrk80ign
    Helmert shift to WGS8431,146,47,0,0,0,0
    proj4
    +proj=longlat +ellps=clrk80ign +no_defs +towgs84=31,146,47,0,0,0,0
    WKT (ESRI)
    GEOGCS["GCS_Merchich",DATUM["D_Clarke_1880_IGN",SPHEROID["Clarke_1880_IGN",6378249.2,293.4660212936269],TOWGS84[31,146,47,0,0,0,0]],PRIMEM["Greenwich",0],UNIT["Degree",0.0174532925199433],AUTHORITY["EPSG","4261"]]

    Sample conversion

    Morocco capital: WGS84 -6.84160, 34.02090 → EPSG:4261 -6.8432095, 34.0235351

    Values are within ±0.1 m at the test point.

    About the Geographic (longitude/latitude) family

    Merchich is a geographic coordinate system: positions are longitude and latitude in degrees on its reference ellipsoid, not metres on a plane. It is the datum layer that projected grids (UTM, national belts) are built upon.

    Because it is unprojected, distances and areas cannot be measured directly from its degrees — convert to a metric projected system (or use a geodesic calculation) first. This page's converter does exactly that.

    Useful links: Converter · Batch converter · File converter · Country page

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    FAQ

    It is the coordinate system “Merchich”, a Geographic (degrees) system in the Geographic (longitude/latitude) family, identified worldwide by the code EPSG:4261.

    You may also need: Arab-world coordinate converter · Surveying file format converter · Batch coordinate file converter