An NFL game is officially 60 minutes long, divided into four 15-minute quarters. However, due to stoppages, timeouts, halftime, and commercial breaks, the average duration of an NFL game from start to finish is about 3 hours and 12 minutes.

Game Structure

• Four quarters of 15 minutes each, totaling 60 minutes of playtime.
• Halftime break lasts about 12 to 13 minutes.
• Two-minute breaks after the first and third quarters allow teams to switch sides.
• The game clock stops frequently for incomplete passes, players going out of bounds, penalties, and timeouts.

Additional Time Factors

• Commercial breaks during television broadcasts significantly extend the game length.
• Replay reviews and injuries can cause further delays.
• Overtime periods add extra time if the score is tied after regulation; regular season overtime is 10 minutes, while playoff overtime can extend indefinitely until a winner is decided.

Live Play Time

• Actual live action with the ball in play is roughly 18 minutes per game, with the rest of the time spent on pauses and breaks.

In summary, while the game clock runs for 60 minutes, the overall real-time duration of an NFL game is approximately 3 hours and 12 minutes on average.