Wii Fit (Wiiフィット^?) is a video game developed by Nintendo for the company's home video game console, Wii, designed by Hiroshi Matsunaga. It is an exercise game consisting of activities using the Wii Balance Board peripheral. Wii Fit is currently the third best selling console game in history (among games not packaged with a console) with 22.61 million copies sold as of May 2010.

The game uses a unique platform peripheral called the Wii Balance Board, on which the player stands during exercise. The game features yoga, strength training, aerobics, and balance games. Matsunaga described the game as a "way to help get families exercising together".Wii Fit has been used for physiotherapy rehabilitation and has been adopted by various health clubs around the world. Additionally, the game has been used in nursing homes to improve posture in the elderly. The game has received generally positive reviews, despite criticism over the lack of intensity in some of its workout activities.

Wii Fit requires the use of the Wii Balance Board, a unique platform peripheral that the player stands upon during play. Similar to a bathroom scale, the Wii Balance Board is capable of measuring a person's weight, but is also able to detect the person's center of balance (COB), a feature heavily utilized in the game. Wii Fit contains more than 40 activities designed to engage the player in physical exercise, which consist of yoga poses, strength training, aerobics, and balance games. Most activities generally focus on maintaining COB and improving posture.