Ratner was born and raised in Miami Beach, Florida, the son of Marsha Pratts (remarried), a socialite, and Ronald Ratner. He grew up in a "middle-class Jewish family". His father was the son of a wealthy Miami businessman. His mother was born in Cuba, and immigrated to the U.S. in the 1960s with her parents, Fanita and Mario Presman (their families had originally moved to Cuba from Eastern Europe). Ratner's mother was sixteen when he was born. Ratner told Aventura Business Monthly in a May, 2011, cover story interview that he "really didn't know" his biological father, and that he considers Alvin Malnik, who opened the famous Forge restaurant in Miami Beach, to be his dad, "the one who raised" him. Ratner's biological father was chronically homeless in Miami Beach, a situation which inspired the adult Brett to become the director and board member of the nationwide nonprofit organization Chrysalis, which helps the homeless find work.
Ratner attended Rabbi Alexander S. Gross Hebrew Academy elementary school and attended Alexander Muss High School in Israel and graduated in 1986 from Miami Beach Senior High School. He is a 1990 graduate of New York University. In 2010, he cited the 1980 boxing film Raging Bull as his inspiration to enter the world of film.
Ratner had directed several music videos and one film, the 1997 action comedy Money Talks, before reaching commercial success with the action-comedy Rush Hour (1998), starring Jackie Chan and Chris Tucker, both of whom reunited with Ratner for two sequels, Rush Hour 2 (2001) and Rush Hour 3 (2007). Ratner was under consideration to direct X-Men (2000) and Superman Returns (2006), although both were eventually directed by Bryan Singer. After Singer left the X-Men franchise to direct Superman Returns, Ratner became director of X-Men: The Last Stand (2006).
Ratner directed a Super Bowl ad for Wynn Las Vegas featuring Steve Wynn (Wynn stood on top of Wynn Las Vegas for the commercial as he introduced the property).
In May 2008, it was announced that Ratner would be directing the long in-development Beverly Hills Cop IV, which was confirmed on December 6, 2013. He also edited the English version of the film Kites, starring Indian superstar Hrithik Roshan and Mexican actress Bárbara Mori using techniques developed in the critically acclaimed series Kung Faux.
Ratner directed and served as an executive producer on the 2011 CBS comedy-drama television series CHAOS. In the same year, Ratner also directed the ensemble comedy caper Tower Heist.
In May 2011, it was announced that Ratner signed on to direct The 39 Clues, the live-action adaptation of the young-adult book series.
Ratner was seen on MTV series Punk'd when Hugh Jackman, who portrays Wolverine in the X-Men films, was the subject of a practical joke that made it appear Ratner's $3.6 million home in Beverly Hills was destroyed by a BBQ grill explosion. Ashton Kutcher later arrived at his home and hugged him after Jackman was punk'd.
On April 25, 2007, Fox Broadcasting announced that he, Carrie Fisher, Garry Marshall and Jon Avnet would be the judges for the network's filmmaking-competition, reality TV series, On the Lot, which premiered to low ratings in May 2007.
He also appeared as himself in Entourage, in an episode that was shot at his actual Beverly Hills home, according to an interview he did in Aventura Business Monthly, and in the film Black and White.
His publishing company, Rat Press, is re-releasing out of print books about Hollywood. The first three books, released on March 25, 2009, are about Marlon Brando, Robert Evans and Jim Brown. Brett Ratner also created his own magazine titled "Ratmag" through celebrity magazine publisher MYMAG.
Ratner produced a remake of Snow White, Mirror Mirror (2012), based on the screenplay The Brothers Grimm: Snow White by Melisa Wallack.
Ratner has produced feature films, TV series, and documentaries. He executive produced the 2010 documentary film, Catfish and the 2011 TV documentary, American Masters: WoodyAllen – A Documentary. Ratner also produced Skyline (2010) and Horrible Bosses (2011).
In December 2012, Ratner and Australian media mogul James Packer formed a joint venture, RatPac Entertainment. The firm will produce independent films and co-produce big-budget films with a major studio. RatPac and Dune Entertainment formed a film investment vehicle, which in September 2013, entered a multi-year, 75-film co-financing partnership with Warner Bros.
In June 2014, Ratner's RatPac Entertainment and Class 5 Films acquired the movie rights to the non-fiction article American Hippopotamus, by Jon Mooallem, about the meat shortage in the U.S. in 1910 and the attempts made by Major Frederick Russell Burnham, Captain Fritz Joubert Duquesne and Congressman Robert Broussard to import hippopotamuses into the Louisiana bayous and to convince Americans to eat them. The movie will highlight the Burnham - Duquesne rivalry, two famous spies who had previously been under orders to assassinate each other. Ratner, Edward Norton, and William Migliore will produce this feature film.
Ratner executive-produced the Rush Hour TV series.
On January 19, 2017, Ratner received a star on the Hollywood Walk of Fame for his contributions to the motion picture industry, located at 6801 Hollywood Boulevard.
On August 4, 2011, the Academy of Motion Picture Arts and Sciences announced Ratner would produce the 84th Academy Awards with Don Mischer. However, Ratner resigned on November 8, 2011 after remarking that "rehearsal is for fags". Ratner later apologized for his remarks. Eddie Murphy, who was scheduled to host the ceremony, also resigned in deference to a new production team. Ratner was replaced by Brian Grazer, and Murphy was replaced by previous Oscar host Billy Crystal.
Ratner's films have received generally mixed reviews.
Ratner has said that he "fear[s] God and respect[s] God and love[s] God," though he does not see himself as religious but rather "spiritual" and "moral".