Kattan was born in Culver City, California. His father, Kip King (1937–2010), was an actor and voice actor who appeared on the series Reno 911! as Larrie Plum. His mother, Hajnalka E. Biro, was once photographed for Playboy and worked as a model in London. His father was Jewish of Iraqi and Polish descent, while his mother, a native of Budapest, Hungary, is a Buddhist. His stepfather was a Buddhist therapist and monk. His half-brother, Andrew Joslyn, is a professional musician and composer. Kattan was raised on a Zen retreat on Mount San Antonio (Mount Baldy), outside Los Angeles. He lived on Bainbridge Island, Washington, where he attended Bainbridge High School, and graduated in 1989.
Kattan was a member of several improvisational comedy (improv) and sketch comedy troupes, one of them being The Groundlings in Los Angeles. His father was an original member of the troupe. Kattan also did some minor roles on TV, including the first episode of the second season of NewsRadio, "No, This Is Not Based Entirely on Julie's Life," as a photo shop employee.
He moved to New York City to work on Saturday Night Live from 1996 to 2003. His recurring characters included Mr. Peepers, Mango, Azrael Abyss, Kyle DeMarco from The DeMarco Brothers, Gay Hitler, Suel Forrester (known for the term "dagitybo") and, most notably, one half of the Butabi Brothers with fellow SNL (and Groundlings) cast member Will Ferrell, known for their trademark head-bobbing. Kattan and Ferrell continued the characters in the 1998 film A Night at the Roxbury.
Kattan was to play Xanthias in the Broadway theatre production of Stephen Sondheim's The Frogs but he was replaced during previews by Roger Bart. Kattan was set to host the game show Gameshow In My Head and even filmed the pilot episode in Hollywood. However, he was replaced with Joe Rogan for the series. Kattan appeared in a Diet Pepsi Max commercial during Super Bowl XLII in 2008 that featured the song What Is Love and had many actors in the commercial performing the head bob from A Night at the Roxbury.
In August 2009, Kattan starred in the Independent Film Channel (IFC) miniseries Bollywood Hero, where he portrays himself and the difficulties he faces after a career as a comic actor, trying to attain leading man status. Starting in fall of 2009, Kattan appeared in a supporting role in The Middle. Kattan played Bob, a colleague of Frankie Heck's at Mr. Ehlert's car dealership. Kattan appeared in an episode of How I Met Your Mother as a star in Wedding Bride, a fictional movie within the show. He played himself acting as Jed Mosely, a character based on the main character Ted with an arrogant personality. He reappeared as the character while the gang was watching its sequel, Wedding Bride 2. On December 17, 2011, Kattan made a guest appearance on Saturday Night Live's Christmas show, hosted by Jimmy Fallon and again briefly on the final episode of SNL's 37th season.
In January 2014, Kattan was a cast contestant who was eliminated 1st in episode 2 of Rachael vs. Guy: Celebrity Cook-Off (hosted by Guy Fieri and Rachael Ray). In June 2014, Kattan reprised his role as former SNL character Mango in a preview of Missy Elliott protégée Sharaya J's "Shut It Down" via a T by Alexander Wang campaign.
In 2017, Kattan was a contestant on season 24 of Dancing with the Stars paired with professional dancer Witney Carson. He was the first celebrity dancer eliminated.
Kattan married model Sunshine Deia Tutt on June 28, 2008, in Oakhurst, California, after proposing to her on Christmas Eve 2006. The couple separated on August 10, 2008, and were officially divorced in February 2009. In February 2014, Kattan was arrested on suspicion of driving under the influence in Los Angeles after his car crossed a barrier of orange cones and flashing signs and plowed into the cushioned back of a maintenance vehicle, authorities said. Video later surfaced of Kattan having to be helped off an airplane that landed in Los Angeles just hours before his arrest. Kattan pled not guilty to the charges in March 2014 and was ordered by a judge to attend twelve-step program meetings.
Kattan revealed he had severely injured his neck, undergoing numerous surgeries. He has refused to provide details on the injury saying instead "It was a stunt thing. I can't get into it with you."A Night at the Roxbury (1998)
House on Haunted Hill (1999)
Any Given Wednesday (2000)
Corky Romano (2001)
Undercover Brother (2002)
Enough About Me (TV movie) (2005)
Adam & Steve (2005)
Santa's Slay (2005)
The Year Without a Santa Claus (2006)
Two Dreadful Children (voice) (2007)
Aqua Teen Hunger Force Colon Movie Film for Theaters (voice) (2007)
Christmas in Wonderland (2007)
Superbad (deleted scene) (2007)
Nancy Drew (2007)
Undead or Alive (2007)
Delgo (voice) (2008)
Tanner Hall (2008)
Hollywood & Wine (2009)
Bollywood Hero (2009)
The Last Film Festival (2010)
Foodfight! (voice) (2012)
Crazy Enough (2013)
Hotel Transylvania 2 (voice) (2015)
Saturday Night Live (1996–2003)
Grace Under Fire (1996)
Celebrity Deathmatch (voice) (as himself) (2001)
Inked (TV) (2005)
Totally Awesome (2006)
Sunset Tan (as himself) (2007)
Hollywood Residential (2008)
The Middle (TV) (2009–2012, 2014)
How I Met Your Mother (2010/2014)
Late Night with Jimmy Fallon (as himself) (2011)
Rachael vs. Guy: Celebrity Cook-Off (as himself) (2013)
The Awesomes (2015)
Jake and the Never Land Pirates (voice) (2015)
Bunnicula (voice) (2016)
Dancing with the Stars (as himself) (2017) contestant on season 24