The news comes 10 days after the Briton was beaten by Jaime Munguia in Phoenix, Arizona.
Ryder previously held the WBO interim super-middleweight title and challenged for undisputed gold against Saul “Canelo” Alvarez in May 2023.
Canelo, fighting in his native Mexico, defeated Ryder on points, before the Briton suffered another loss to a Mexican in January, when Munguia stopped the “Gorilla” in round nine.
“It is with a heavy heart that I have come to the decision to hang up my gloves and retire from professional boxing,” Ryder said in a statement on Tuesday (6 February).
“I’ve been absolutely blessed to have the most amazing career over the past 14 years. Starting in Bethnal Green in 2010 and ending in Phoenix, Arizona. I’ve been lucky enough to box everywhere from the O2 Arena, T-Mobile in Vegas, Alexandra Palace, Manchester Arena, to Guadalajara in Mexico. For a boy from Islington, it’s been some run.
“Although I didn’t manage to win that world title, I’ve achieved and experienced more than I could ever have imagined when I first put on a pair of boxing gloves, and I wouldn’t change that for any belt.”
Ryder proceeded to thank his coaching team, promoters and “loving family”. The southpaw said: “My partner Nancy [and] kids Heidi and Brody have given me the strongest ‘why’ possible over the past decade in this sport. I’m blessed to have you all in my corner.”
Ryder also confirmed his next move, saying: “Although my professional career as a boxer is now over, the sport won’t be able to get rid of me that easily, and I look forward to officially starting my new career as a coach working alongside Tony [Sims] at the Matchroom Gym very shortly. There’s no place like home.”
Ryder’s most notable win arguably came against Daniel Jacobs in 2022, as the Briton won a split decision against the former world champion in London.