Foxes are classified as omnivores, not carnivores. As an omnivore, a fox eats meat but also eats fruits and leaves.
An omnivore is an animal that eats all kinds of foods. Humans are omnivores, as are foxes, bears, skunks and many species of turtles. Even if an animal exists primarily on meat, as long as they regularly consume other foods, they are classified as omnivores.
For meat, foxes primarily eat insects and small vertebrates such as birds and reptiles. They will also eat eggs, when the opportunity arises. The crab-eating fox will even search out crabs on floodplains as part of its diet. Most fox species will eat about 2.2 lb of food a day and bury the rest for later use.