He currently voices the Ice King in the Cartoon Network animated series Adventure Time, and voices additional characters on Scooby-Doo! Mystery Incorporated. He also voices Quantum Ray in Cosmic Quantum Ray Plastic Man in Batman: The Brave and the Bold and Leo Callisto in Miles from Tomorrowland As of 2007, he hosted the TV show Funday Night at the Movies on Turner Classic Movies (TCM) which encourages children to watch old movies.
He was the lead vocalist for the Syracuse, New York-based band The Tearjerkers since the early 1980s, when he replaced the original vocalist Buddy Love. Other members of The Tearjerkers included Charlie Robbins, Dave DeCirce, and Dave Soule, who is still active in the central New York music scene. "Syracuse Summer" is the group's best-known song, and is included on The History of Syracuse Music, Volume XII and XIII. While the Tearjerkers did not become a national act, one Tearjerkers roadie would go on to achieve fame: comedian Bobcat Goldthwait. Goldthwait's film Shakes the Clown features Kenny as Shakes' bitter archrival. In 1980, Kenny was briefly a member of Syracuse-based pop punk band The Trend along with Goldthwait.
Kenny appeared regularly on NBC's music video show Friday Night Videos, in a recurring comedic Music News segment. In 1991, he took over as the show's regular host until being replaced later that year by Frankie Crocker.
In 1996, Kenny appeared along with his wife, Jill Talley, in the music video for Tonight, Tonight by The Smashing Pumpkins, playing a young couple taking their honeymoon on the moon. The video was very popular, winning six MTV Video Music Awards. Kenny also appeared in the music video for "Sing" by the band Travis.
In 2006, Kenny co-wrote and recorded SpongeBob SquarePants: The Best Day Ever with producer Andy Paley. Kenny's singing on the CD is done in the voice of SpongeBob SquarePants and other characters from the show. Other musical artists on the CD include: Brian Wilson, Tommy Ramone, and Flaco Jiménez. The music pays homage to The Beach Boys, The Archies, The Lovin' Spoonful, and The Troggs, among others.
Kenny has acted in many films and TV shows, debuting in How I Got Into College (1989) and later he appeared in films such as Shakes The Clown and Comic Book: The Movie. He appeared in sketch comedies The Edge and Mr. Show. He also appeared in the live-action segments of SpongeBob SquarePants as Patchy the Pirate.
Although most famous for being the voice of SpongeBob SquarePants since the series premiere in 1999, in "Help Wanted." Tom Kenny has voiced many characters in over 200 productions. It was revealed by Kenny, that his favorite character to voice for, was Slinkman in Camp Lazlo. Kenny said that he voices "a lot of sweet yellow characters for some reason."
He is known to provide the voice of the various meows of Gary the Snail in SpongeBob, but he played his first set of voice actor roles for Rocko's Modern Life, primarily as Heffer Wolfe. Joe Murray auditioned Kenny for voice acting roles for the series in a casting call in Los Angeles, California. On one occasion, the producers required Kenny to fill the role of Charlie Adler, who was absent on that occasion. In addition, Kenny had to perform one song and learn how to play another song within ten minutes due to time constraints. He said that this helped him believe that he could stand "toe to toe" with other voice actors. He also voices Cupid for the Nick show Fairly Odd Parents.
Joe Murray chose Kenny for a voice acting position in Camp Lazlo as Lumpus and Slinkman, because Murray, after seeing Kenny's previous work for Rocko's Modern Life, felt that Kenny "adds writing to his roles" and "brings so much."
He was the voice of Dog in CatDog, as well as the voice of Cliff. He also had a few roles in The Powerpuff Girls TV show. He was the Mayor, the Narrator, Mitch Mitchelson, Snake and Little Arturo from the Gangrene Gang, Rainbow the Clown, etc. He voices Eduardo, and various other characters in Foster's Home For Imaginary Friends. He plays a number of roles in the Transformers Animated TV show. A few of the characters he voices in this series are Starscream and his clones, Isaac Sumdac, and Waspinator. He is also the voice of the Autobots Skids and Wheelie in the live-action Transformers film series. He has voiced the Penguin on the The Batman. On Dilbert, Kenny voiced Ratbert, Asok and other one-time characters. He played Mr. Hal Gibson in the animated kids show Super Robot Monkey Team Hyper Force GO! He is also Yancy Fry and various minor characters on Futurama.
In 2009, Kenny became a regular cast voice in the Fox comedy series Sit Down, Shut Up. He voices Muhammad Sabeeh "Happy" Fa-ach Nuabar, the secretive custodian who is plotting a terrorist attack, as well as Happy's interpreter. The series premiered on April 19, 2009. Kenan Thompson, Kristin Chenoweth, Jason Bateman, Nick Kroll, Cheri Oteri, Henry Winkler, Will Arnett and Will Forte are the other main cast members.
He also voiced the Best Buy elf from the retail stores' Christmas TV commercials.