In the first film, Kirby reluctantly joins the appliances on a mission to find Rob, who is referred to them as "the Master." While seemingly being cantankerous and bossy towards the others, he actually cares very much about them, and risks his life to save them more than once. Kirby cannot help but keep up appearances, considering that he is independent and often held back by the others.
Being grumpy and stubborn, Kirby doesn't hang around much with the other appliances until near the very end of the first movie. He utterly despises Blanky and his overly-emotional personality. However, Kirby starts to soften up as the film progresses. In the movie's sequels, he is more laid-back and closer to his fellow appliances.
- Kirby is named after Jim Kirby, the founder of the brand "Kirby", but in the novella by Thomas M. Disch, he is named after William Henry "Boss" Hoover, the founder of the brand "Hoover".
- Kirby is the final voice role for Thurl Ravenscroft.
- It is revealed in The Brave Little Toaster to the Rescue that if Kirby sucks up kitty litter, he will get nauseous and end up vomiting, which he does off-screen.
- It is also revealed that he likes to dance, but gets embarrassed when others are watching him.
- In Disch's original novella The Brave Little Toaster Goes to Mars, Kirby stayed behind with Lampy while the other appliances went on the mission. In the film, they join them on the quest.
- There is a cameo of Kirby and his friends in the series The Oz Kids in the episode "Christmas in Oz".
- On nearly every video and DVD cover for all three movies, Kirby's head is incorrectly colored pink. In the films, Kirby's head is gray.