Gobstoppers, also known as jawbreakers in the United States, are a type of hard candy. They are usually round, and usually range from 1 to 3 cm (0.4 to 1.2 in) across; though gobstoppers can be up to 8 cm (3.1 in) in diameter.

The term gobstopper derives from "gob", which is slang in the United Kingdom and Ireland for mouth. The sweet was a favourite among British schoolboys in the first half of the twentieth century—author Roald Dahl, who wrote about a jar of gobstoppers featuring in the prank he played in his local sweet shop in 1923, also referred to them in his fictional Everlasting Gobstopper which was featured in his 1964 children's novel Charlie and the Chocolate Factory.

Gobstoppers usually consist of a number of layers, each layer dissolving to reveal a differently coloured (and sometimes differently flavoured) layer, before dissolving completely. Gobstoppers are too hard to bite without risking dental damage (hence the name "jawbreaker").

Gobstoppers have been sold in traditional sweet shops for at least a century, often sold by weight from jars. As gobstoppers dissolve very slowly, they last a very long time in the mouth, which is a major factor in their popularity.