Video report by ITV News Correspondent Neil Connery
Known for his flamboyant dress sense, McCririck became a feature of TV racing coverage during the 1980s.
Prior to that he worked for the Sporting Life newspaper and in recent years he had appeared on At The Races.
He also starred on many reality TV shows such as Celebrity Big Brother and Celebrity Wife Swap.
McCririck is survived his wife of 48 years, Jenny.
McCririck, who worked for ITV and later for Channel 4, was well known for his outlandish dress sense and his ebullient personality in the betting ring.
More often than not, he had a large cigar in hand as he outlined the prices for the upcoming races.
He took Channel 4 to an employment tribunal in 2013 claiming he had been sacked as a presenter because of his age.
But the tribunal later ruled he was dismissed as his pantomime persona was 'unpalatable'.
ITV Racing presenter Matt Chapman described McCririck as a "class journalist in his day" and the "best betting ring commentator there's ever been".
And BBC horse racing correspondent Cornelius Lysaght described McCririck as "a one-off" and a "Marmite character".
He first took part in Celebrity Big Brother in 2005 along with Caprice Bourret, Germaine Greer, Jackie Stallone, Bez and Kenzie.
He caused controversy with his views on women but was back to take part in Ultimate Big Brother, featuring housemates from previous series.
McCririck also appeared on Celebrity Wife Swap - where former politician Edwina Currie tried to get him to cook and clean.
His appearance on Big Brother's Bit On The Side in October last year shocked viewers, with some pointing out he was looking "gaunt" and "poorly" compared with how he looked during his time as a contestant.
He then revealed he felt he had "no purpose in life" after his regular television work came to an end and explained that the dramatic change in appearance was down to intentional weight loss and a severe bout of flu.
According to his family, McCririck's interest in horse racing and betting began at Harrow where he was the school bookie.
On leaving, he worked for an illegal street bookmaker then legally on-course where he learned the art of tic-tac, clerking bets and making a book.
Ascot Racecourse released a statement saying it was "deeply saddened" by the death of McCririck.
"Everyone at Ascot is deeply saddened to hear of the passing of John McCririck," it tweeted.
"He was an unmistakable presence in racing, and one of the most impactful broadcasters of his generation."
The British Horseracing Authority paid tribute to McCririck, tweeting: "Throughout a lengthy and colourful career, one thing was always clear - his enduring passion and love for the sport of horse racing.
"He was a recognisable figure and resonated with the wider public. Our condolences go to his family."
Record-breaking former jockey Tony McCoy tweeted: "Very sad to hear the news of John McCririck's passing - one of the most recognisable faces from the world of horse racing and a great at promoting our sport."
Race goers at Sandown described him as an "absolute character" who "livened up the place".
Richard Hoiles ITV News Racing lead commentator said McCririck could "command" a room but his flamboyant character did not detract from his knowledge and passion of the sport.
"He was the face of racing for a whole generation who associated his antics on a Saturday afternoon with the sport that they tuned into watch. And as a result he was probably wider than just the sport itself," Hoiles told ITV News.
"But that shouldn't underpin the fact that he really was meticulous in his preparation, he really did know his subject. He was an award winning journalist and an award winning broadcaster and he was at the top of his game, even though at times he used to create this sort of pandemonium to suggest it was rather less prepared than it was."
His family said: "In this time, he transcended the world of racing, appearing on numerous mainstream TV news and light entertainment programmes including Question Time, The Weakest Link, Celebrity Wife Swap and Celebrity Big Brother in 2005 and 2010."