Blackett will take up the role officially in October to coincide with the beginning of the academic year. She is a graduate of the university herself, having gained a BA in Geography in 1992 as well as an honorary degree in 2015.
Toksvig steps down from the position after a five-year term in office.
Graham Galbraith, the university’s vice chancellor, praised Blackett’s abilities in both business and creativity, traits he believes reflect “the ethos of all that we do”.
He said: “As the University celebrates its 25th anniversary this year, we look forward to welcoming Karen as our new chancellor. I am personally delighted that Karen has agreed to become an important part of our University at such an exciting time.”
Blackett added: “I am honoured to become Chancellor of the University. As an alumna of Portsmouth, I am thrilled to be able to return to the University and use my passion for developing talent and learning, to help create our next set of leaders.”
The chairwoman is not new to the world of education and young people, having established MediaCom’s apprenticeship scheme for 18-24-year-olds in 2012. The programme is the first of in the media sector to be government approved.