Strahan, Anderson Cooper, Seth Meyers, Josh Groban, Neil Patrick Harris and numerous other celebrities have been appearing alongside Ripa as guest co-hosts since longtime "Live!" star Regis Philbin left the morning program last fall.
Strahan has been rumored for weeks to be his permanent replacement. Starting Tuesday, the show will be called "Live! with Kelly and Michael."
"It's time for a new era of our show to begin," Ripa said on the show Tuesday. "It gives me great pleasure to introduce to you the newest member of our 'Live!' family -- Michael Strahan!"
"I adore you and I am so happy to be here and be a part of this," Strahan said. "You know how they say it's a dream come true? I truly can't say that because I didn't even know I could dream this."