Cracknell attended Forest School in London and later went on to Pembroke College, Oxford. While at Oxford, his short story "Alternative Medicine" was published by Margaret Drabble in the first series of The Mays.
Prior to launching his own consultancy in 2008, he covered politics for newspapers for over 15 years, including stints at the Sunday Telegraph, Press Association and finally being political editor at The Sunday Times. He also helped found Sunday Business with Jeff Randall in 1998.
In 23 May 2004 he revealed the doubts of Foreign Secretary Jack Straw that tactics in Iraq were "heavy handed".
On 8 August 2004 it was revealed that Sir David Omand, the UK's intelligence and security coordinator, had told a meeting of the British cabinet he was launching a major leak inquiry, which ended up costing an estimated £1m. 
Following his departure from The Sunday Times, he was a Managing Director at PR firm FD, formerly Financial Dynamics, as well as being Chairman of its public affairs division, where he advised Northern Rock on its recovery plan following the bank being taken into public ownership.
He left in August 2008 to found his own communications firm, Big Tent Communications, of which he is Managing Director.
Cracknell lives in London and Rye, East Sussex and is married with three children.
- "The Enterprise Forum About us". Archived from the original on 20 September 2011. Retrieved 19 August 2011.
- "Media Diary". The Guardian. London. 22 July 2007.