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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
    Convert from this system now

    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.

    Related systems

    Useful links: Converter · Batch converter · File converter

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    FAQ

    What is EPSG:4646?
    It is the coordinate system “Grand Comoros”, a Geographic (degrees) system in the Geographic (longitude/latitude) family, identified worldwide by the code EPSG:4646.
    What datum does it use, and how accurate is it?
    It is based on the intl ellipsoid and it carries Helmert parameters to WGS84. The residual at the test point is about ±0.1 m versus PROJ; for centimetre work use a geodetic adjustment service.
    Where is this system used?
    It is used in Comoros. This page shows its area of use as a coordinate rectangle above.
    How do I convert EPSG:4646 to WGS84?
    Use the free coordinate converter above (preloaded with this system) to convert to WGS84, UTM, or any other system, within a ±0.1 m residual.

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