The money that Google makes in a day is estimated to be at least $100 million dollars per day from their advertising program Adwords alone.
Then they have other revenue streams such as google products and services such as the Chromebook and anything else they sell.
Google is estimated to make $300 million dollars or more per day.
There's no way to know for sure unless you work at or own the company and you'd have to work in the accounting department.
But I do know that Google makes a heck of a lot of money per day and per year.
Of course they do have employees to pay to keep things running so they need that revenue to pay for all that stuff.