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    EPSG reference

    EPSG:4206 — Agadez

    Agadez (EPSG:4206) — a Geographic (degrees) system on the clrk80ign datum, used in Algeria. Parameters, proj4, WKT, accuracy ±0.1 m, plus a free converter to WGS84 and U…

    At a glance

    EPSG
    4206
    Name
    Agadez
    Kind
    Geographic (degrees)
    Family
    Geographic (longitude/latitude)
    Ellipsoid
    clrk80ign
    Accuracy
    ±0.1 m (vs PROJ)
    Countries
    Algeria
    Convert from this system now

    Area of use

    West0.16°
    South11.69°
    East16.00°
    North23.53°

    Projection parameters

    Projectionlonglat
    Ellipsoidclrk80ign
    proj4
    +proj=longlat +ellps=clrk80ign +no_defs
    WKT (ESRI)
    GEOGCS["GCS_Agadez",DATUM["D_Clarke_1880_IGN",SPHEROID["Clarke_1880_IGN",6378249.2,293.4660212936269]],PRIMEM["Greenwich",0],UNIT["Degree",0.0174532925199433],AUTHORITY["EPSG","4206"]]

    Sample conversion

    Centre of the area of use: WGS84 8.08000, 17.61000 → EPSG:4206 8.0800000, 17.6100000

    Values are within ±0.1 m at the test point.

    About the Geographic (longitude/latitude) family

    Agadez 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 · Country page

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    FAQ

    What is EPSG:4206?
    It is the coordinate system “Agadez”, a Geographic (degrees) system in the Geographic (longitude/latitude) family, identified worldwide by the code EPSG:4206.
    What datum does it use, and how accurate is it?
    It is based on the clrk80ign ellipsoid with no default transform to WGS84 (ballpark). 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 Algeria. This page shows its area of use as a coordinate rectangle above.
    How do I convert EPSG:4206 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