Brad Pitt has revealed that he will show his new film, 12 Years A Slave, to his children - but only when they are old enough to understand the subject.

The father-of-six, who plays a Canadian carpenter in Steve McQueen's slavery drama, admitted he would only screen it to his 11-year-old son Maddox at the moment.

"Absolutely. Maybe my eldest I would [show it to] right now," he told The Today Show.

"I'd rather for the others to get a little bit older and understand the dynamics of the world a little more."

Chiwetel Ejiofor, Michael Fassbender, Benedict Cumberbatch and Paul Dano are among the star-studded ensemble cast in the film, which is based on Solomon Northup's autobiography.

"It's one of those few films that cuts to the base of our humanity," the actor said.

Brad, who is engaged to Angelina Jolie, also joked that he is "too busy" to think about turning 50. He will celebrate the milestone on December 18.

"We'll see. I'm busy right now so I haven't thought about it," he said.

As for ageing, he added: "So far I haven't minded a bit. So I have no complaints."