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I made a shapefile from a DEM raster of Ethiopia, and I want to find the total area of the shapefile. I have changed the CRS of all files to Africa_Albers_Equal_Area_Conic (ESPG: 102022), and the units are meters. I have tried using the field calculator, but the answers are very small. I have also used the identify features tool, and the answers are the same as the field calculator's.

I also used "count" in the field calculator to get the number of pixels, but these sometimes seem very small too. The pixel size is 0.000277778,-0.000277778, but I don't know what the units are, so I am not sure how to use that to find the area.

enter image description here enter image description here enter image description here enter image description here enter image description here CRS Units

I tried using the measure area tool where you draw a polygon, but this gave a very small answer too. enter image description here

I read there might be a way to do it with GRASS, but I have a problem with my GRASS plugin which I don't understand. enter image description here enter image description here

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    I think something's gone wrong in your reprojection to Albers. Take a look at the scale at the bottom. 1:62 - are the distances on the screen really only 62x larger in real life?
    – phloem
    Commented Apr 25, 2018 at 18:55
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    It looks like you used the wrong method for changing the projection. Check out the answer to this question: gis.stackexchange.com/questions/280489/…
    – csk
    Commented Apr 25, 2018 at 18:56
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    Your pixel sizes will not be so small once you correctly project into an SI-based projection (i.e. meters). They are currently in degrees (e.g. epsg:4326)
    – Jon
    Commented Apr 25, 2018 at 19:13

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