Carr has dual citizenship - British and Irish. He was born in London to Irish immigrant parents. He has a degree in political science from the University of Cambridge. He lives with his girlfriend, Karoline Copping, in North London. She works for Channel Five. Carr is an atheist. He used to be a Christian. Importantly, because of his religion, he did not have sex until he was 26. He stopped being a Christian in his mid-20s.