The Imitation Game star is dad to 16-month-old son Christopher, and is expecting a second child with his wife Sophie Hunter.
Benedict, who is known for closely guarding his personal privacy, opened up about becoming a parent for the first time during an interview on British TV show This Morning on Wednesday, admitting it's a big learning curve.
Asked if becoming a father is his "proudest achievement", Benedict replied: "It's probably Sophie's. I'm expecting a second child now... I'm still proving myself as a father."
Read more: Benedict Cumberbatch to be a father for the second time
The Brit is most famous for his role as super sleuth Sherlock Holmes in the BBC miniseries, but is making a name for himself as a movie star with his role in new comic book adaptation Doctor Strange.
However, he has yet to have his son Christopher influence the kind of roles he chooses to take on, admitting: "He's very small..."
In the new Marvel adventure, Benedict stars as neuroscientist Stephen Strange, who finds himself with super powers when a car crash leads him on a journey of healing and into a new, mystical world of discovery.
Read more: Benedict Cumberbatch welcomes son
While the film is vastly different to the actor's usual projects, he was attracted to the plot because of its variety.
"It was an acting challenge on every level; action, comedy, everything you want in a film," he smiled.
One thing Benedict won't be doing anytime soon is appearing on U.K. talent show Strictly Come Dancing. His close friend Robert 'Judge' Rinder is currently competing on this year's series, and while Benedict is a fan of watching him in action, he has ruled out an appearance on the programme himself.
"He's so fantastic on Strictly. He's a friend. I've seen him as Judge Rinder, but I know him as Rob," he said.
And asked whether he would want to try his luck on Strictly, Benedict laughed: "I've not got dancing feet."
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