New City Gas in Montreal plays host to the festivities, where all 26 competitors successfully made weight.
Among those weighing in were UFC welterweight champion Georges St-Pierre (170 pounds) and interim titleholder Carlos Condit (169), whose title-unification bout headlines Saturday's pay-per-view event at Montreal's Bell Centre.
"Just to come back, I missed this so much," said St-Pierre, a French-Canadian fighter who competes for the first time in 19 months. "You guys can't believe it. I'm going to give you a great show. Don't miss it."
Welterweight contenders Johny Hendricks and Martin Kampmann, who meet in the co-headliner, also hit the scale and each weighed 171 pounds.
The full weigh-in results included:
MAIN CARD (Pay-per-view, 10 p.m. ET)
Champ Georges St-Pierre (170) vs. interim champ Carlos Condit (169)
Johny Hendricks (171) vs. Martin Kampmann (171)
Tom Lawlor (184) vs. Francis Carmont (185)
Constantinos Philippou (185) vs. Nick Ring (184)
Mark Hominick (145) vs. Pablo Garza (145)
PRELIMINARY CARD (FX, 8 p.m. ET)
Patrick Cote (185) vs. Alessio Sakara (186)
Cyrille Diabate (206) vs. Chad Griggs (205)
Mark Bocek (156) vs. Rafael dos Anjos (155)
John Makdessi (155) vs. Sam Stout (154)
PRELIMINARY CARD (Facebook, 6:20 p.m. ET)
Antonio Carvalho (145) vs. Rodrigo Damm (145)
John Maguire (171) vs. Matt Riddle (170)
Azamat Gashimov (135) vs. Ivan Menjivar (135)
Darren Elkins (145) vs. Steven Siler (145)