Farming Simulator community for some odd reason has this "4x map", "16x map", "64x map" terrain size measuring culture. It makes no sense to try to tell someone your terrain size by referring into some other terrain (giants default terrain size) and multiply its size to reach yours. How could anyone think of such weird cumbersome and WRONG way.
Proper terrain sizes are listed as KILOMETERS (km), for example kilometers x kilometers would be good way to say what size your terrain is. In regular chat etc conversations this is almost always shortened to single number "km" for example 2km, 4km or 8km etc. Some people write 4km x 4km as well which is perfectly fine, its a real numbers in the long format.
If your terrain size is not even number like 2 or 4 kilometers, for example large terrains of 8.1km, it is still perfectly fine to sum them up as "my terrain is 8km", that 0.1 value doesn't make much difference and lazy people never would type such details. Even with huge 16.3km terrains its perfectly fine to say "my terrain is 16km".
When you say "my terrain size is 8km" it means exactly that, no weird references, no make belief nonsense, just clear and direct size value.
Practical examples: ravenport and felsbrunn are 2km x 2km (so in short "2km"), Midwest Horizon is 4km x 4km (so in short "4km") and Pleasant Valley Industries (PV19) is 8.1km x 8.1km (so once again in short "8km" as we get the idea of it being 8.1km).
In short: say "2km" or "8km" etc short and simple ACTUAL sizes.
You can also create terrains with odd sizes like 3km, 5.1km, 7.1km, 10.2km etc which alone should make it clear this "EX" thing is completely wrong. FS19 terrains are NOT restricted to power of two ie 2, 4, 8, 16, 32 etc sizes, it is very important to understand this. See unitsPerPixel for more info.
PMC is working on several irregular sized terrains: 1km, 3km, 5.1km, 7.1km, 10.2km and 20.4km
Please stop using "EX" thing as it doesn't mean anything, its wrong. You don't want to use wrong sizes now do you?
But! but! everyone else uses "EX" too!?, well if everyone else jumps off the bridge, would you?