Maynard stepped on the scale first and checked in at 155 pounds. Edgar followed and made the bout official by weighing in at 154½ pounds.
The bout will be the third meeting between these two. Edgar has never beaten Maynard.
In their first bout, a non-title affair in April 2008, Maynard outmuscled Edgar and took him down repeatedly en route to a unanimous decision.
When they met for a second time in January, Edgar was the UFC 155-pound champion. Maynard dominated the first round, registering a pair of knockdowns.
But Edgar recovered quickly in the second round, using his speed and elusiveness. The following three rounds were closely contested and the fight ended in a split draw.
"I'm ready to do this, I'm going to get this kid," Edgar said after stepping off the scale. "I'm all for the anti-bullying movement."
Maynard's nickname is 'The Bully.'
Aldo will be making the second defense of his belt under the UFC banner, and fourth since claiming the title in WEC. Florian fights for the second time at featherweight.
This fight will mark Florian's third attempt at becoming a UFC champion. His previous two tries came as a lightweight.
"It's going to be a great fight," Florian said. "It's the fight that brought me to 145. I've trained too hard and too long not to go home with the title (Saturday) night.
All other fighters made weight, including those appearing on the main card.
Middleweight contender Brian Stann removed all of his clothing, while being shielded by a towel, to shed a half-pound. He would then tip the scale at 186 pounds.
His opponent Chael Sonnen had no difficulty making the fight official. He weighed in at 185½ pounds.
Highly-rated lightweight contender Melvin Guillard and Joe Lauzon both weighed in at 155½ pounds for their three-round bout. Guillard is one of the fighters often mentioned as an opponent for the Edgar-Maynard winner.
Franklin McNeil covers mixed martial arts and boxing for ESPN.com. Follow him on Twitter at www.twitter.com/Franklin_McNeil.