So, I'm trying to calculate the theoretical max wattage of everything plugged into my outlet. (Only have one wall socket in this room and need to carefully manage what's connected.)

I've currently got a 1000VA UPS (which is rated for 600W at full load, which, despite using for three years, I've recently discovered firsthand is already too low) which I use for my PC and monitor.

Since I'm going to need to be upgrading that soon to at least a 1200VA or 1400VA UPS for a new PC build (and probably should before a the new build anyway), I'm curious about how to calculate total usage for everything drawing power.

My question really is, when calculating how much power is being drawn from the wall outlet in addition to the regular stuff (chargers, etc.), do I only calculate the UPS, do I not include the UPS in the calculation, or do I calculate all three (PC PSU, monitor, UPS)?

Obviously, not everything is at full load, so I won't be drawing that much, but this is just a theoretical calculation of potential full load.