Label polygon with area units in QGIS
If you want to label a polygon in QGIS showing the area it covers, but you don't have a column in your attribute table that has the area value, how do you do it? It's simple in QGIS - you can just use $area as the label value and then if you want to format it so that it has a certain number of decimal places you can use format_area($area,1), for example.
Just be sure to check what units your data are in before you start. If your data is in decimal degrees then it would be best to convert it to a coordinate reference system that uses metres.
See my intro and intermediate QGIS courses for more: https://www.udemy.com/user/alasdair-r...