"The last 11 years with the All Blacks Sevens has been an awesome ride that I've loved every minute of," he said. "I've built life-long friendships with players, coaches and management and got to experience the high of success on the international stage. I want to thank all those who have helped and supported me on the way, from club level right through to the national side.
"Sevens means you're on the road a lot. While I got to travel and represent my country, sacrifices were made at home. I want to thank my wife and kids and family and friends for their enormous support, and I am looking forward to being around a lot more.
"Today starts my new life after footy. I'm looking forward to finishing my Master's degree, which examines what makes successful coaching from an athlete's perspective, and my goal is to one day coach a national side."
New Zealand Rugby chief executive Steve Tew said Forbes' retirement was the end of an era.
"DJ has been an integral part of an incredibly successful All Blacks Sevens outfit that defined the way the game is played," Tew said. "His natural leadership saw him take on the captaincy of the team during a period of triumph and his knowledge of sevens and calm wisdom will be sorely missed."
All Blacks Sevens coach Clark Laidlaw said Forbes was an inspiration to the team.
"DJ's contribution to sevens has been as big as any. His consistency of performance over a long-playing career is unheralded. What impresses me is DJ's ability to always play at his very best and lead by example, regardless of the circumstances. We wish him the best of luck for the future."