Fitness may refer to:

• Physical fitness, a state of health and well-being of the body
• Fitness culture, a sociocultural phenomenon surrounding exercise and physical fitness
• Fitness (biology), an individual's ability to propagate its genes
• Fitness (cereal), a brand of breakfast cereals and granola bars
• Fitness (magazine), a women's magazine, focusing on health and exercise
• Fitness and figure competition, a form of physique training, related to bodybuilding
• Fitness approximation, a method of function optimization evolutionary computation or artificial evolution methodologies
• Fitness function, a particular type of objective function in mathematics and computer science
• "Fitness", a 2018 song by Lizzo

See also

• FitNesse, a web server, a wiki, and a software testing tool
• Survival of the fittest