A football (also known as a football ball, soccer ball, or association football ball specifically in the United Kingdom) is the ball used in the sport of association football. The name of the ball varies according to whether the sport is called "football", "soccer", or "association football". The ball's spherical shape, as well as its size, weight, and material composition, are specified by Law 2 of the Laws of the Game maintained by the International Football Association Board. Additional, more stringent standards are specified by FIFA and subordinate governing bodies for the balls used in the competitions they sanction.

Early footballs began as animal bladders or stomachs that would easily fall apart if kicked too much. Improvements became possible in the 19th century with the introduction of rubber and discoveries of vulcanization by Charles Goodyear. The modern 32-panel ball design was developed in 1962 by Eigil Nielsen, and technological research continues to develop footballs with improved performance. The 32-panel ball design was soon joined by 24-panel balls as well as 42-panel balls, both of which improved on performance prior to 2007.

A black-and-white patterned spherical truncated icosahedron design, brought to prominence by the Adidas Telstar, has become a symbol of the sport. Many different designs of balls exist, varying both in appearance and physical characteristics.