Calzaghe admitted he had been forced to take "one of the toughest decisions of my life" but said his desire to write his name in the record books alongside Rocky Marciano by retiring as an undefeated world champion helped him make up his mind.
The Welshman, who won all 46 of his professional fights, said: "There's always the temptation to fight on, especially if you are the champ and no one has ever beaten you.
"But I've come to a point where the satisfaction of retiring undefeated has to outweigh the thrill of another fight."
Calzaghe's last fight was a dazzling points win over Roy Jones in New York in November 2008, a contest which fulfilled his final remaining boxing ambition of headlining a show at Madison Square Garden.
A triple ABA champion as an amateur, Calzaghe claimed his first world title when he outpointed Chris Eubank to win the WBO super-middleweight belt in Sheffield in 1997.
He would go on to make 21 straight defences of that title but it was later in his career when he gained the wider respect he craved, outclassing unbeaten Mikkel Kessler to unify the 12st titles and then edging past light-heavyweight great Bernard Hopkins in Las Vegas.
In addition, Calzaghe showed his achievements had truly transcended his sport when he won the BBC Sports Personality of the Year award in 2007, and was awarded the CBE in the Queen's Birthday Honours List.