Actor Michael Fassbender says he was so convinced he was miscast as tech mogul Steve Jobs that he considered getting out of the movie.

The movie star was handed the role after Leonardo DiCaprio and Christian Bale reportedly passed it on.

Fassbender says he initially thought he had taken on too much by signing on for Danny Boyle’s biopic when he first read through screenwriter Aaron Sorkin’s script, reported Contactmusic.

Talking to reporters at the Toronto International Film Festival in Canada, where he was honoured with a career retrospective, Fassbender said, "He (Sorkin) wrote all that stuff! It was so dense! It was such a mountain, and I’m a slow learner, so when the script arrived for me and the opportunity came to play the part, I really thought, ‘This is not me. This should be somebody else. It’s a miscast scenario’.

"In rehearsals, I was trying to find a way to get out of the job. I remember telling my driver, ‘If I put my arm in the door, you should slam it. It should cause a break and it should get me out of this gig’." 

The performance in Boyle’s film about the late Apple boss went on to earn Michael an Oscar nomination.