Vorderman was born in Bedford, the youngest of three children of Dutch father Anton 'Tony' Vorderman and Welsh mother Edwina Jean. Vorderman was educated at the Roman Catholic comprehensive Blessed Edward Jones High School in Rhyl. At the age of seventeen she went to Sidney Sussex College, Cambridge, in 1978, where she studied Engineering and gained a third class honours degree at age 20. Vorderman initially found employment as a junior civil engineer at Dinorwig Power Station in Wales and later as a graduate management trainee in Leeds. In her spare time she was briefly a backing singer along with friend Lindsay Forrest in the Leeds-based pop group Dawn Chorus and the Blue Tits, fronted by radio DJ Liz Kershaw during the early 1980s. During 1984/85 she made regular appearances on the Peter Levy show on Radio Aire, appearing mid-morning to read a story for any pre-school children who might be listening with their mothers.
Vorderman's mother noticed a newspaper advertisement asking for a woman with good mathematical skills to appear as co-host on a quiz show for the fledgling fourth terrestrial channel and submitted an application on behalf of her daughter. Aged 21, Vorderman made her name on Countdown with Richard Whiteley from the show's inception in 1982 until Whiteley's death in June 2005. In June 2005 the producers of Countdown asked Vorderman if she wanted to fill the role of main presenter vacated by the recently deceased Richard Whiteley. Vorderman declined, and a search for a new presenter began while the show went into a four-month hiatus. In October 2005, Des Lynam replaced Whiteley and co-hosted with Vorderman. In January 2007 Des O'Connor replaced Lynam; Vorderman continued to co-host the show.
Between 1987 and 1989 Vorderman co-hosted BBC TV series Take Nobody's Word For It with Professor Ian Fells and was chosen to compère the world chess championship match between Garry Kasparov and Nigel Short in 1993. She also had a long stint presenting on CITV's facts and science show How 2 from 1990–1996. Vorderman has worked as a researcher and producer on many shows, specialising in science and educational programmes and has presented several other television programmes including the BBC's Tomorrow's World.