Brian Grazer is producing from a screenplay by John Hoffman.
81-year-old Hefner has reportedly approved Ratner's vision.
"Hef came from a puritanical upbringing and reinvented himself to be the godfather of the sexual revolution," Ratner said.
"He also used his magazine to advocate civil rights and free speech, and put James Brown on his show 'Playboy After Dark' when they didn't put black performers on national television. He broke all kinds of taboos, especially in sexuality. I want to show it all, from the First Amendment struggles to his first orgy to the stroke in the 1980s that almost killed him."