Inspector Gadget is the titular main protagonist of the cartoon series and movies of the same name. He is also known as Jonathan "John" Brown. An advanced cyborg equipped with many gadgets (from where his name is derived), he protects the world from the villainous Doctor Claw and his M.A.D. henchmen and is a mix of bumbling super-spy Maxwell Smart (who is coincidentally portrayed by his deceased voice actor Don Adams) and dim-witted detective.
The gadget has straight black hair and gray eyes.
In the 1982 pilot episode, Gadget had a mustache, but it was later removed due to MGM threatening to sue DIC Entertainment as he looked too similar to Inspector Clouseau.
Gadget's attire resembles that of Inspector Clouseau's attire from the early Pink Panther movies from 1963 to 1982.
He wears a gray trench coat with a dark grey fedora, white shirt, blue tie and pants, and dark brown gloves and wears gray shoes.
In Inspector Gadget Saves Christmas and Inspector Gadget's Field Trip, he has the same appearance from the original cartoon.
In The Super Mario Bros. Super Show! live-action segment episodes, "Defective Gadgetry" and "Treasure of the Sierra Brooklyn", he wears a brown fedora, light brown trench coat, white shirt, black tie, brown gloves, blue pants, and black shoes.
In the live-action films, he wears a brown fedora, light tan trench coat, white shirt, black tie and pants, and black shoes and wears no gloves. He also has a Riverton Police Department badge on his belt. but in Inspector Gadget 2, He wears a grey coat that resembles the one from the cartoon.
In Gadgets and the Gadgetinis, He wears the same clothes in the cartoon, but he wears a black trench coat instead of grey, He also wears yellow gloves and his fedora is light gray instead of dark gray, but also retains his blue tie and pants and wears dark gray shoes.
In the 2015 cartoon, Gadget has the same appearance from the original cartoon. Albeit much thinner.
Inspector Gadget is a bumbling, incompetent, gullible and somewhat clever man. He is half-human, half-cyborg, meaning he is a cyborg. He believes his enemies are his allies and vice versa.
- Whenever Gadget gets electrocuted, he has a visible skeleton shown despite being a cyborg.
- "Defective Gadgetry" of The Super Mario Bros. Super Show! marks the first time Inspector Gadget appears in live-action, predating the 1999 live-action film by ten years.
- In the third episode of the 2015 reboot, Gadget states that in his younger days he was an singer. He is very visibly an adult in the flashback and it also took place in the 1970s. Seeing this his birthdate can be considered from 1952 - 1962.