The former England captain, who opted to follow his old mentor Sir Alex Ferguson into retirement, will play his final game for Paris Saint Germain on May 26, ending one of the most high-profile careers in world football.
And Ferguson is sure that, at 38, Beckham, who spent a decade under the Scot at Old Trafford, has made the right decision.
"He's picked the right time," Ferguson said.
"He's won the league again with PSG and he is exactly the same as myself in that he'll have plenty of things to do.
"Fashion will be his role I would imagine, but he's a young man and he'll certainly have plenty of things to do."
Ferguson paid tribute to Beckham, who after leaving United went on to win league titles in Spain, the United States and now France.
"He is an amazing person and when it comes to longevity and reinventing himself - David has been absolutely incredible," Ferguson said.
"When he went to America there wasn't a person in this place who thought he would really have a career.
"Yet he still went on and played for his country and for Milan and PSG in European ties.
"The one thing he always had was unbelievable stamina.
"He could run all day and that has allowed him to stay in the game and play for his country into his mid-30s."