Tom Hardy doesn't think there's a ''harder job on the planet'' than parenting.

The 40-year-old actor may have a highly successful, yet demanding, career in the film industry but he has admitted there's nothing more challenging than raising his two children - a 10-year-old son called Louis with his ex-girlfriend Rachel Speed and a two year old with his wife Charlotte Riley - because his father role is so ''important.''

Speaking to Esquire magazine, he said: ''There is no harder job on the planet, and more important, than parenting.

''You've got the military, police, doctors, service personnel - massive respect, huge consequences - but parenting? It's beyond a job, isn't it.''

However, his career has had more of a physical effect on him as his knees are getting stiffer, his hair is turning grey and he's locked horns with too many people.

He explained: ''My knee's gone, the nerves are shot, I'm getting white hair...

''I've got battle scars from rubbing my nose in the wrong places, banging heads with the wrong people, being difficult or whatever it is.

''But I've got to the point where I'm responsible as well. If you come to me I can find, delegate, help, create a solution. I'm not a tearaway any more.''

Tom always knew from when he was a child that he would make a ''living out of being away with the fairies'' because he wasn't very good academically.

He said: ''If you took me as my academic self, I was an epic f***ing failure.

''I probably wasn't focused on the person asking me the question, and in that moment they were like, 'Well, we can't talk to this kid, he's away with the fairies.'

''And I've made a living out of being away with the fairies, but at 11 how can you feel sure what the future holds?''