print-composerqgisqgis-2qgis-2.2qgis-2.4
For work I always have to create a table with my name, project name, date etc. into my map layouts. I also need to include the scale like "1:150000" in that table.
So far I am solving that by including an html table with the html box function of the print composer. Is there a way to automatically include the right scale? So far I only managed to automatically include the date by using a little javascript. Maybe something similar is also possible for the scale?
In QGIS it's not called Reference Scale.
You can make sure line thickness and font size are visually the same in the map canvas and the print composer (regardless of paper size and extent) if you size your font labels and line styles using Map Units instead of points, mm, etc...
There is also the option to use non-map units, and in that case you can just set the map canvas scale to match whatever scale you want to print at to get a quick visual (but not if your map takes a while to render).
Best Answer
Tested with QGIS 3.6.1
As mentioned in the documentation, you can create a label and insert this code to get the current scale for the map with the item name
Map 0: