Depending on who they advertise with, how many page views the adverts get and any other arrangements it could be anywhere between $50000 and $500000. I wouldn't like to guess an actual number.
I was looking for that website! And yes - factoring those costs in (which is nigh on impossible without asking the owners of ArmorGames) it will be a lot less.
I don't know how accurate those estimate websites are. Because that is all they are after all: estimates. No member here really knows how much the site brings in, and I don't even have the slightest clue.
who gets the cash? the game makers or site makers?
Both. Obviously, the people who have built and work on the site need to get paid to maintain it. And also, AG sponsors many game developers as well as full-time developer employees. So you pretty much have to figure that all of those employees would in fact, be monetarily compensated.