John Dezso Ratzenberger, born on April 6, 1947, in Bridgeport, Connecticut, is an American actor best known for his role as Cliff Clavin on the comedy series Cheers. This role earned him two Primetime Emmy nominations.

He also played the character in the short-lived spin-off The Tortellis and in an episode of Wings. He has voiced various characters in several Pixar animated feature films, including Hamm in the Toy Story franchise, The Abominable Snowman in the Monsters, Inc. franchise, Mack in the Cars franchise, The Underminer in The Incredibles franchise, and Fritz in the Inside Out franchise.

John Ratzenberger began his entertainment career while living in London in the 1970s. He acted in and wrote film and television through the 1970s and early 1980s before returning to America. At an audition for a role in a new sitcom, he created the character of Cliff Clavin. Cheers, which aired from 1982 to 1993, was a success and went on to run for 11 years.

After Cheers, he began voicing characters for Pixar, with his first role being Hamm in Pixar's debut feature film Toy Story in 1995. He continued to voice characters in many subsequent Pixar films.

His personal life includes his marriage to Georgia Stiny in 1984, with whom he had two children before divorcing in 2004. He later married Julie Blichfeldt in 2012. He lived in London for 10 years before moving to Vashon, Washington, in 1994. He is of Austrian, Hungarian, and Polish descent.

He attended St. Ann's School and Bassick High School in Bridgeport and then Sacred Heart University in Fairfield, Connecticut. In 1969, he worked at the Woodstock Festival as a heavy equipment operator and as part of the crew building the stage. He is an avid sailor, shooter, fisherman, and billiard player. He plays the drums and belongs to a bagpipe band as part of the Emerald Society. He lives in Connecticut with his wife Julie.

His career is marked by his versatility and talent. He began acting in the 1970s and has portrayed a wide range of characters in both television and film. His notable roles include Cliff Clavin in Cheers, Hamm in the Toy Story franchise, and the Abominable Snowman in the Monsters, Inc. franchise.

He has also appeared in films such as A Bridge Too Far, Superman, Superman II, Star Wars: The Empire Strikes Back, Outland, and Gandhi. Ratzenberger's performance as Cliff Clavin earned him two Primetime Emmy nominations for Outstanding Supporting Actor in a Comedy Series in 1985 and 1986.

He also won the TV Land Legend Award for Cheers in 2006 and was nominated for the MovieGuide Grace Award for Most Inspiring Movie Acting for What If... in 2011.