The Fight Club star has vowed to cherish the coming months with his fiancee Angelina Jolie and their six children before reaching the half-century milestone on 18 December, 2013.
He tells People.com, "This is what I think about: 'OK, you're way over the mid-point (of your life). You don't know how much time you have left.' I want to enjoy this year more than ever."
Pitt has been keeping busy looking after his brood while Jolie tends to professional commitments, and admits he is relishing fatherhood.
He adds, "It's been a family type of year, a down-home type of year. Mama's worked more. And quite frankly I've really enjoyed it. (Parenting) takes you right off yourself."