Voice work
Ratzenberger has contributed voice work for animated projects.
Ratzenberger has voiced characters in 24 Pixar films. His roles include:
Hamm the piggy bank in the Toy Story series (1995, 1999, 2010, 2019, 2026)
P.T. Flea, the Circus Ring Leader in A Bug's Life (1998)
Yeti the Abominable Snowman in the Monsters, Inc. series (2001, 2013)
The school of Moonfish in Finding Nemo (2003)
The Underminer in The Incredibles series (2004, 2018)
Mack the truck in the Cars series (2006, 2011, 2017)
Mustafa the waiter in Ratatouille (2007)
John the Axiom passenger in WALL-E (2008)
Tom the construction worker in Up (2009)
Gordon the Dunbroch palace guard in Brave (2012)
Fritz the mind worker in the Inside Out series (2015, 2024)
Earl the Velociraptor in The Good Dinosaur (2015)
Bill the crab in Finding Dory (2016)
Juan Ortodoncia the deceased dental patient in Coco (2017)
Fennwick the cyclops construction worker in Onward (2020)
According to Ratzenberger, Pixar's tradition of including him as a good luck charm in every film beginning with the studio's first film, Toy Story, was due to him becoming good friends with former Pixar filmmaker John Lasseter, who directed or executive-produced each of the first 20 Pixar films. Ratzenberger's tenure at Pixar was parodied during the end credits of Cars, where his character, Mack, watches car-themed versions of Pixar films (Toy Car Story, Monster Trucks, Inc., and A Bug's Life, the latter of which references the Volkswagen Beetle). Mack notes that all the characters that John Ratzenberger has played had excellent voice actors until he realizes that they are performed by the same actor, at which point he remarks, "They're just using the same actor over and over," and asks, "What kind of a cut-rate production is this?!" The practice of regularly casting Ratzenberger in Pixar films was so well-known that his characters also occasionally shared the same voice actor in languages other than English, notably Renato Cecchetto who dubbed nearly all of Ratzenberger's Pixar roles for the Italian versions of the respective films. Ratzenberger has stated that his favorite Pixar roles were Hamm from the Toy Story series and P.T. Flea from A Bug's Life.
Following Lasseter's exit from Pixar, Ratzenberger revealed at Motor City Comic Con in May 2024 that he was not a fan of the regime that replaced Lasseter or the studio's subsequent films, claiming "[...] they suck", and was critical of the political messaging that he felt was being placed in the films. Pixar's 23rd feature film, Soul (2020), was the first Pixar film that did not involve Ratzenberger himself, though it featured a character animated in his likeness as a cameo according to the film's co-director Kemp Powers; the cameo was also confirmed by director Pete Docter on the film's audio commentary track. After voicing a character in each of Pixar's first 22 films, Toy Story (1995) through Onward (2020), Ratzenberger would not have another role in any Pixar film except for sequels in which he reprised roles he previously played such as Fritz in Inside Out 2 (2024) and Hamm in Toy Story 5 (2026). Ratzenberger would also reprise previous Pixar roles in new television series produced by Disney Television Animation rather than Pixar, including Yeti (now named Adorable) and a new character named Bernard in Monsters at Work (2021–24), and Mack in the upcoming Cars: Lightning Racers (2027).
Ratzenberger has also continued to work with Lasseter, who produces all feature films and executive-produces all series at Skydance Animation. Ratzenberger has appeared in every Skydance Animation feature film and series to date. His roles include:
Rootie the tropical juice bar-owning bad luck root in Luck (2022)
Caruncle the alien shopowner in WondLa (2024, 2025)
Milo the monster handler in Spellbound (2024)
An elder Javan bird in Swapped (2026)
An undisclosed role in Ray Gunn (2026)
Aside from Pixar and Skydance animated productions, Ratzenberger voiced Harland the jet tug in Disneytoon Studios' Planes (2013), and Brodi the plane in its sequel, Planes: Fire & Rescue (2014), which are spin-offs of Pixar's Cars series and executive-produced by Lasseter. Additionally, Ratzenberger provided the voice for Aniyaku the assistant manager in the English dub version of Studio Ghibli's Spirited Away (2002), which Lasseter also executive-produced.
