StarCraft2: Easy way to calculate number of harvesters

The easiest way to count harvesters is probably going to be to double click on a worker mining at each base. A full page is 24 workers and don't forget to add one for each geyser you have going (the double click won't select the worker currently inside of it). Just add up the results from there and it should be pretty close at least.

If you want your full worker count, you can also look at the bottom left to see your idle worker count and if for some reason it is not zero, then presumably these will have been missed by your mining worker counting and can be added as well. Other than that you are probably only going to miss a couple guys currently building things if you are terran. As far as non-mining workers though, this will really mostly apply to terran and even then will probably never average higher than 3 workers.

As for production, you should really never stop scv/probe production unless one of the following is true:

• You are planning a one or two base push and are at your desired number of workers for it.
• You absolutely have to to stay alive.
• You have in excess of ~70-75 workers.

The 70+ workers is enough to give you three bases worth of decent saturation while leaving enough room for an army.

As zerg things get trickier as you don't have a building dedicated to worker production, but since you didn't mention drones I won't get into that for now.

The pro way is to know exactly how many military units you have out and how much supply they use; from there, you know your harvester count because it's (supply total - military supply).

Also, with the "select all harvesters" approach you mention, other units don't enter into it if you double-click on a harvester to select all of them on the screen, rather than drawing a rectangle. (Faster, too.) Non-harvesting harvesters still confound that count though.

Nowadays, one can just hover over the supply indicator and popout will appear with army and worker counts.