Ball was born in Bristol where he attended Kingswood Primary School on the eastern edge of the city. Later in his childhood the family moved to Bolton, Lancashire, where he attended Bolton County Grammar School. He left formal education with two "O" Levels, one in mathematics and one in geography. He then signed on for three years in the Royal Air Force, worked as a Butlin's Redcoat, and was an entertainer in northern clubs and cabaret. He was nicknamed Johnny after John Ball, who played for Bolton Wanderers from 1950 to 1958 and the name stuck for the rest of his life.
Television and radio career
Ball was a regular fixture on children's television from the mid 1970s and throughout the 1980s, presenting several series of popular science and technology programmes intended for children. He was also one of the hosts of infant education programme Play School beginning in 1967 and continuing throughout the 1970s and beyond. As well as appearing on screen Ball wrote jokes for some shows including Crackerjack. All of these shows appeared on the BBC. Ball's shows were renowned for presenting scientific and technological principles in an entertaining and accessible way for young people. In 2003, he appeared on The Terry and Gaby Show in which he answered viewers' questions. In July 2004, he was named in the Radio Times list of the top 40 most eccentric TV presenters of all time. In July 2012, he presented a Horizon special on ageing on BBC Four. He has starred in ITV and Channel 4 television adverts as well as radio adverts for the Yorkshire-based firm Help-Link. Ball's daughter Zoë presents for BBC TV and presents the breakfast show on BBC Radio 2. His son Nick is a film director. Ball lives with his wife Di in Buckinghamshire. In 2012, Ball took part in the Strictly Come DancingTV show, where he was paired with Aliona Vilani. A training accident in the three-week interval resulted in torn ligaments for Vilani, causing her to retire temporarily from the show. She was replaced by Iveta Lukošiūtė who, with Ball, went on to be eliminated in the first week. Vilani returned in the final group dance alongside Ball. In a TV interview in October 2017, Ball claimed Vilani faked the injury, with Vilani denying the allegation and saying she would take legal advice over Ball's comments. He was 74 at the time, and he is the oldest contestant in the show's history.
Series guide
Think of a Number
Pilot: 2 April 1977
Series 1: 6 editions – 12 April 1978 – 17 May 1978
Series 2: 6 editions – 12 September 1979 – 17 October 1979
Series 3: 6 editions – 10 September 1980 – 15 October 1980
Series 4: 6 editions – 15 September 1982 – 20 October 1982
Series 5: 6 editions – 4 January 1984 – 8 February 1984
Series 6: 6 editions – 26 September 1984 – 31 October 1984
Think Again
Series 1: 5 editions – 9 January 1981 – 6 February 1981
Series 2: 6 editions – 8 January 1982 – 12 February 1982
Series 3: 6 editions – 7 January 1983 – 11 February 1983
Series 4: 6 editions – 13 September 1983 – 18 October 1983
Series 5: 6 editions – 10 September 1985 – 15 October 1985
Think!Backwards
Five editions shown over one week – 28 September 1981 – 2 October 1981
Think! This Way
Five editions shown over one week – 28 March 1983 – 1 April 1983
Think It... Do It
Series 1: 6 editions – 11 March 1986 – 15 April 1986
Series 2: 6 editions – 27 February 1987 – 3 April 1987
Knowhow
Series 1: 6 editions – 8 March 1988 – 12 April 1988
Series 2: 6 editions – 25 October 1988 – 29 November 1988
Series 1: 7 editions – 14 June 1989 – 26 July 1989
Series 2: 6 editions – 3 August 1990 – 7 September 1990
Series 3: 7 editions – 18 March 1992 – 29 April 1992
Series 4: 7 editions – 5 July 1993 – 16 August 1993
Series 5: 5 editions – 8 August 1994 – 1 September 1994
Other activities
Ball is in favour of nuclear power and has given speeches arguing for its development. and has rejected the notion of man-made climate change, arguing that carbon dioxide has been unfairly victimised in the debate. On 15 December 2009, Ball was booed off stage at a show "in celebration of ... science" in London for comments sceptical of anthropogenic climate change hypotheses.
In November 2006, Ball voiced his opposition to the Safeguarding Vulnerable Groups Act, which would require any adult working with children to be vetted by the Criminal Records Bureau. In an interview with The Sunday Times, he said: "It is like George Orwell's 1984... a quarter of adults will have to be checked... The fear we are instilling in is abhorrent."
Ball is a supporter of the FatallyFlawed campaign against the use of plug-in socket covers.
In April 2014, Ball donated his time and talent as voice-over in an educational animated video for the Raspberry Pi Foundation, a Cambridge-based UK charity whose aim is to get children interested in taking up a career in computer programming.
On 30 November 2019, Ball appeared as a surprise guest with Robert Rinder in the Midnight Gameshow section of Michael McIntyre's Big Show.