In 1968, the Motion Picture Association of America replaced the so-called Hays Code, instituted in the 1930s to enforce moral guidelines upon cinematic content, with its own rating system — ushering in the age of the R-rated film. 

An R rating, which might be applied to a film for some combination of violence, nudity, sex, foul language, or substance abuse, meant that it was forbidden to those under 16 unless accompanied by a parent or adult guardian (the age was later changed to 17). The first title to earn such a rating was the 1968 noirish thriller “The Split,” about a robbery gone awry. However, previous blood-soaked classics like “Bonnie & Clyde” and “The Good, the Bad and the Ugly” got an R retroactively.

Late-1960s features such as “Easy Rider” and “The Wild Bunch” — both rated R — similarly dialed up the explicit content and mature themes. Quickly and gloriously, a new era of American filmmaking, effectively unencumbered by censorship, was taking shape. Check out the best R-rated movies of all-time.

Jump ahead a few decades and R-rated content is more or less ubiquitous across screens both big and small. Not only that, but the rating’s boundaries have been pushed to their furthest possible reaches. There has also emerged an ample slate of R-rated blockbusters, many of which opened to rave reviews. From “The Godfather” to “300” to “Deadpool” and its popular sequel, these films pulled a few punches on their way to massive success. (Speaking of “Deadpool” — these are the highest-grossing movies in the Marvel universe.)

Click here to see the most successful R-rated movies of all time

Which ones have been the most successful of all? To determine the most successful R-rated movies of all time, 24/7 Tempo reviewed box office and production budget data from The Numbers, an online movie database owned by consulting firm Nash Information Services. Though both domestic and worldwide box office are given, movies were ranked according to lifetime worldwide box office earnings as of June 2021, adjusted for inflation.