People often say, "It takes a lot of faith to be an atheist." This is usually followed with a statement like, "After all, you can't be 100% certain there is no God."
As an atheist, I can say that it has never taken me any faith at all to be one. Saying that being an atheist requires faith requires one to accept the idea that everyone thinks God is real, when in fact many people (called atheists) do not. It is the very definition of atheism. Atheists are people who don't think God is real.