The Ukrainian has been fighting professionally since 1996, winning 64 of his 69 fights with 53 by knockout.
Dr Steelhammer rose to prominence at the 1996 Olympics, where he won gold, before winning his first world title, the WBO heavyweight, in 2000.
Klitschko said: “I deliberately took a few weeks to make my decision, to make sure I had enough distance from the fight at Wembley Stadium.
“As an amateur and a professional boxer, I have achieved everything I dreamed of, and now I want to start my second career after sports.”
Praise has been flooding in for Klitschko, not just because of his prowess in the ring, but also the way he acted outside of it.
Like his style or not, Wladimir Klitschko was heavyweight champion, won 64 of 69 fights - and was an absolute gentleman along the way.— Mike Anstead (@mike_anstead) August 3, 2017
What a career and what an athlete Wladimir Klitschko was. Very few have earned the right to retire like he has— Chris Hames (@ChrisHames11) August 3, 2017
The 41-year-old went unbeaten for 11 years before losing his final two fights, conceding his IBF, WBA and WBO titles when being outpointed by Tyson Fury before being stopped by Joshua in the 11th round at Wembley.
Even in the second of those defeats the Ukrainian recovered from a fifth-round knockdown to heavily drop Joshua for the first time in his professional career.
That final fight – he has chosen not to exercise his rematch clause – was widely considered the most entertaining at heavyweight since the glamour era of the 1990s, and was also perhaps the biggest since Lennox Lewis overcame Mike Tyson in 2002.
For that reason, among others, some fans think his retirement has come at the perfect time.
🥊 69 fights
🥇 64 wins
👊🏽 53 KOs
While at his peak, around the time of his one-sided, 2011 victory over David Haye, Klitschko held three of the four world heavyweight titles, at a time when his older brother Vitali was the WBC champion.
In his retirement statement Klitschko hailed boxing for giving him the opportunity to travel the world, learn new languages, start businesses and “help people in need”.
His retirement also means that Joshua will most likely fight mandatory challenger Kubrat Pulev, of Bulgaria, while Klitschko ensures his legacy remains intact as one of the finest heavyweights in history.
🥊 One of the greatest 😉August 3, 2017