Forza Motorsport is a racing game with extensive customizability, similar to the Gran Turismo series. There are 30 tracks and over 230 cars with a unique feel that can be modified to the smallest details, from spoilers to decals, and the option to create your own shapes with 100 different layers for a single car. Every single part influences the car behavior - even the G-forces are taken into account, with a realistic damage model.

The game modes include a career mode with different classes, time trials, free runs and arcade races. In the career mode, winning races unlocks manufacturer relationships and you can earn money to buy new cars or customize your vehicles. This mode is expanded over Xbox Live with human opponents.

Forza also includes Drivatar technology, where you can train the computer AI to copy your driving skills (the way you approach corners, the amount of brake applied) and then let the AI race for you to move quickly past certain courses. Over Xbox Live, you can organize your own competitions, start a car club with a team of drivers, exchange cars, download ghost cars to improve your race times, compete on over 1400 leaderboards and acquire new car setups.