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    EPSG reference

    EPSG:4646 — Grand Comoros

    Grand Comoros (EPSG:4646) — a Geographic (degrees) system on the intl datum, used in Comoros. Parameters, proj4, WKT, accuracy ±0.1 m, plus a free converter to WGS84 and…

    At a glance

    EPSG
    4646
    Name
    Grand Comoros
    Kind
    Geographic (degrees)
    Family
    Geographic (longitude/latitude)
    Ellipsoid
    intl
    Accuracy
    ±0.1 m (vs PROJ)
    Countries
    Comoros

    Area of use

    West43.16°
    South-11.99°
    East43.55°
    North-11.31°

    Projection parameters

    Projectionlonglat
    Ellipsoidintl
    Helmert shift to WGS84-963,510,-359,0,0,0,0
    proj4
    +proj=longlat +ellps=intl +no_defs +towgs84=-963,510,-359,0,0,0,0
    WKT (ESRI)
    GEOGCS["GCS_Grand Comoros",DATUM["D_International_1924",SPHEROID["International_1924",6378388,297],TOWGS84[-963,510,-359,0,0,0,0]],PRIMEM["Greenwich",0],UNIT["Degree",0.0174532925199433],AUTHORITY["EPSG","4646"]]

    Sample conversion

    Centre of the area of use: WGS84 43.35500, -11.65000 → EPSG:4646 43.3455367, -11.6465080

    Values are within ±0.1 m at the test point.

    About the Geographic (longitude/latitude) family

    Grand Comoros 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

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    FAQ

    It is the coordinate system “Grand Comoros”, a Geographic (degrees) system in the Geographic (longitude/latitude) family, identified worldwide by the code EPSG:4646.

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