What is the Salary Cap
The NFL salary cap is a limit on how much money each team can pay its players in a single season. Every NFL team must stay under this cap amount when adding up all player contracts. The cap was created to help keep teams competitive and prevent wealthy teams from spending unlimited money on the best players.
How the Salary Cap Amount is Determined
The salary cap is calculated based on the total revenue the NFL makes each year from television deals, ticket sales, merchandise, and other sources. The NFL and the players union agree on what percentage of this revenue goes toward player salaries. This is typically around 48 percent of league revenue. As the NFL makes more money, the salary cap goes up the following year.
Why Teams Have a Salary Cap
The salary cap keeps the league competitive by preventing rich teams from simply buying the best players. Without a cap, teams in large cities with more fan support could spend far more money than smaller-market teams. The cap helps ensure that all 32 teams have a fair chance to compete and build winning rosters.
How Teams Manage the Cap
Teams use various strategies to stay under the salary cap, including trading players, releasing high-paid veterans, and negotiating longer contracts that spread payments over more years. General managers must carefully plan their spending to build competitive teams while following the rules. Teams that go over the cap face financial penalties and loss of draft picks. 
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