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I have a polygon layer. I toggled to edit mode. I added a new column, while number (integer) and called it "area". I then use the field calculator - geometry - $area to populate the polygon area for my polgyons.

Under Layer Properties - first tab - the unit is millimetre

In metadata tab: Extents: In layer spatial reference system units : xMin,yMin 114.53,-38.7888 : xMax,yMax 153.639,-9.22883 Layer Spatial Reference System: +proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs

Can anyone tell me what the area is calculated in? km2, acres, hectares or what?

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closed as unclear what you're asking by underdark Nov 2 '13 at 22:54

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question.If this question can be reworded to fit the rules in the help center, please edit the question.

It isn't obvious what tool you are using (we could guess, but we shouldn't need to). Can you edit your question (just click edit above) to identify the tool. In this case, the answer also depends on what the data source (coordinate reference system) is, so that would also be good information to include in your question. – BradHards Apr 29 '13 at 3:20
This may help you. – Sibi Apr 29 '13 at 3:24
See also here: – julien Nov 3 '13 at 12:18

The unit for calculated area is square unit of whatever the linear unit is. check the properties of your polygon. there you can figure out the linear unit of the layer.

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