The price is $218,000 more than what memorabilia collector Jeff Rosenberg paid for the gloves in 2014.
Rosenberg called owning the gloves over the past two years "an honor" and said he was satisfied to know the person who bought them "values them like I do, and they will now be in a good home."
The buyer was not publicly disclosed.
Shortly after Ali's death in June, Rosenberg decided he was going to auction off the gloves, but said he wasn't pleased about it.
"No matter what the price, there's going to be a sense of loss," Rosenberg said at the time. "It's a connection to the greatest fight."
Both Ali and Frazier came into the bout undefeated, as Ali entered his third fight after a 3?-year suspension for avoiding the draft. Ali lost the fight by decision in 15 rounds.
Despite the fact that the gloves were supposed to be the property of Jerry Perenchio, the Los Angeles-based talent agent never took the gloves. They instead became property of Ali's trainer and cornerman, Angelo Dundee.
Rosenberg, owner of memorabilia company Tri-Star, consigned the gloves to Goldin Auctions, which originally put the gloves in its live auction in Atlantic City, New Jersey, earlier this month. Goldin hoped bidding on the gloves would surpass $1 million, but the auction failed to meet its reserve, so the gloves were moved to the company's online auction that closed early Sunday morning.
The highest price received for a pair of Ali gloves is $836,500 in 2014, for the gloves he used in his first fight against Sonny Liston in 1964.
Ali's gloves weren't the only piece from the "Fight of the Century" sold on Sunday. A jock strap believed to have been worn by Frazier in the fight sold to an undisclosed buyer for $10,200.
Michael Jordan game-used jerseys also continued to rise in price. Goldin sold a game-used Jordan uniform from the 1992 Olympics and a game-used 1996-97 Chicago Bulls uniform, each for more than $60,000.