The rules in detail

The field and the goalposts

The field is 120 yards long including both end zones and 53⅓ yards wide. Yard lines are painted every five yards and numbers every ten, counting up from each goal line to the 50 at midfield.

The hash marks tell officials where to spot the ball: if a play ends near the sideline, the next one starts level with the nearest hash mark. In the NFL they are 18 feet 6 inches apart, the same width as the goalposts.

The goalposts stand at the back of each end zone: two uprights 18 feet 6 inches apart on a crossbar 10 feet high. A field goal or extra point is good if the ball goes over the crossbar and between the uprights or their imaginary extension.

Game length and the clock

Four 15-minute quarters, with a halftime break of about 13 minutes after the second. Teams switch ends after the first and third quarters.

The game clock stops on an incomplete pass, when the ball carrier goes out of bounds, after a score, a change of possession, a penalty or a timeout. After a runner goes out of bounds, the clock restarts when the official spots the ball, except in the last two minutes of the first half and the last five minutes of the second, when it waits for the next snap.

The play clock gives the offense 40 seconds from the end of the previous play to snap the ball, or 25 after certain stoppages such as a timeout. If it runs out, it is delay of game: a 5-yard penalty.

Each team has three timeouts per half. With two minutes left in each half, the officials stop play for the two-minute warning.

Coin toss and kickoffs

Before the game there is a coin toss. The winner chooses to receive, to kick or to defer its choice to the second half; the other team picks which end to defend.

Each half starts with a kickoff, and teams also kick off after every touchdown and its try and after every field goal. Since 2024 the NFL has used the so-called dynamic kickoff: the kicker kicks from his own 35, his teammates line up at the opponent’s 40, and most of the receiving team waits between its own 30 and 35. Nobody but the kicker and the returners may move until the ball hits the ground or a player in the landing zone, between the receiving team’s 20 and its goal line.

A kick that reaches the end zone in the air and is not returned is a touchback, and the receiving team starts at its 35; if the ball first bounces in the landing zone and ends up in the end zone, at its 20. A kick that lands short of the landing zone or goes out of bounds gives the receiving team the ball at its 40.

An onside kick, the short kick the kicking team uses to try to recover the ball, must be declared in advance and is reserved for the team that is trailing.

Downs, formations and the snap

The offense has four downs to gain 10 yards from where the series started. The distance is checked with the ten-yard chain carried by the chain crew on the sideline; when it is close, the chain comes onto the field for a measurement.

Before the snap the offense must have at least seven players on the line of scrimmage and stay set for at least one second. At the snap only one player may be in motion, and never toward the line.

Interior linemen, wearing numbers 50 to 79, may not catch passes unless they report to the referee as eligible.

Nobody may enter the neutral zone, the length of the ball separating the two teams, before the snap. If an offensive player moves, it is a false start; if a defender is in the neutral zone, offside. Both cost 5 yards.

Passing

Only one forward pass is allowed per play, thrown from behind the line of scrimmage. Lateral or backward passes can be made at any time; if they hit the ground, the ball is still live and anyone can recover it.

For a catch to count, the receiver must control the ball, get both feet (or any body part other than his hands) down in bounds and keep control long enough to make a move common to the game.

Pass interference: while the ball is in the air, neither the defender nor the receiver may stop the other from playing it. Defensive pass interference gives the offense the ball at the spot of the foul with a first down, or at the 1 if it happens in the end zone. Offensive pass interference costs 10 yards.

A quarterback who throws the ball where no receiver is, just to avoid a sack, is called for intentional grounding: loss of down and the ball spotted where he threw it (a safety if he was in his own end zone). It is not a foul if he is outside the tackle box and the pass reaches the line of scrimmage.

Quarterbacks get special protection: hitting them late, in the head or at the knees is roughing the passer, 15 yards and a first down.

When a play ends

In the NFL, a ball carrier who falls without being touched can get up and keep going. The play ends when he touches the ground with anything other than his hands or feet after contact by an opponent, goes out of bounds, scores, or when the official rules his forward progress stopped.

A quarterback may slide feet first to end the play; from that moment he cannot be hit.

If a player loses the ball before the play ends, it is a fumble: the ball is live and anyone can recover it.

Scoring in detail

Touchdown: it is enough for the ball, in a player’s possession, to break the vertical plane of the goal line. On a pass, the receiver must complete the catch inside the end zone.

Try: after a touchdown a team chooses to kick from the 15 (1 point) or run a play from the 2 (2 points). If the defense takes the ball the other way into the end zone, it scores 2 points.

Field goal: 3 points. A miss gives the opponent the ball at the spot of the kick, or at its own 20 if the kick came from closer.

Safety: 2 points for the defense when the ball carrier is downed in his own end zone or the offense commits certain fouls there. The team that gave up the safety then kicks off from its own 20.

Common penalties

The team that was fouled may accept the penalty or keep the result of the play. If a penalty would move the ball more than half the distance to the goal line, only half that distance is applied.

False start

5 yards. An offensive player moves before the snap.

Offside, encroachment

5 yards. A defender is in the neutral zone or touches an opponent before the snap.

Delay of game

5 yards. The offense doesn’t snap the ball in time.

Too many men on the field

5 yards. A team has more than 11 players on the field.

Offensive holding

10 yards. A blocker grabs and restricts a defender.

Defensive holding

5 yards and an automatic first down.

Illegal contact

5 yards and a first down. A defender contacts a receiver more than five yards downfield before the pass is thrown.

Defensive pass interference

Ball at the spot of the foul and a first down; at the 1 if it happens in the end zone.

Offensive pass interference

10 yards.

Illegal block in the back

10 yards.

Face mask

15 yards. Grabbing and twisting or pulling an opponent’s face mask.

Unnecessary roughness

15 yards. Late hits, hits out of bounds or on defenseless players.

Roughing the passer

15 yards and a first down.

Unsportsmanlike conduct

15 yards. Two in the same game mean the player is ejected.

Instant replay

A head coach can ask for a play to be reviewed by throwing a red flag. He has two challenges per game and a third if the first two are successful; if a challenge fails, he loses a timeout.

Scoring plays, turnovers and everything in the last two minutes of each half and in overtime are reviewed from the booth without a challenge. The league’s replay officials can also help the referees fix clear and obvious errors.

Overtime

In the regular season, a game tied at the end of regulation goes to a 10-minute overtime. Since 2025, both teams get a possession even if the first one scores a touchdown; after that, the next score wins. If it is still tied after 10 minutes, the game ends in a tie.

There are no ties in the playoffs: 15-minute periods are played until there is a winner, again with a guaranteed possession for each team.

Standings and tiebreakers

Standings are ranked by winning percentage; a tie counts as half a win and half a loss.

When two teams in the same division finish level, the tie is broken in this order: head-to-head, record within the division, record in common games, record within the conference and strength of victory (the combined record of the teams they beat). Further steps include strength of schedule and points, and finally a coin toss.

For wild-card spots between teams from different divisions, the order changes: after head-to-head, if they met, the conference record comes before the record in common games.

The playoffs

Seven teams per conference qualify. The four division winners are seeded 1 to 4 by record; the three wild cards, the best remaining teams, are seeded 5, 6 and 7.

Only the top seed in each conference gets a first-round bye. The Wild Card round pairs 2 vs. 7, 3 vs. 6 and 4 vs. 5; in the Divisional round, the highest remaining seed hosts the lowest. The higher seed always plays at home.

The AFC and NFC champions meet in the Super Bowl, at a neutral site chosen years in advance.