The AFL field is 50 yards long (excluding two 8-yard end zones) and 85 feet wide. In terms of an NFL field, this is half as long and, for some reason, 53.125% as wide. Players are not made to scale.
Field and Equipment
Goal posts are 9 feet apart with the crossbar set at 15 feet (NFL goalposts are 18 feet apart with the crossbar at 10 feet). Missed field goals and kickoffs that bounce off the posts and safety nets are still in play.
Sideline barriers are 4 feet tall and made of high-density foam rubber. The floor outside the barriers, where receivers often land, is made of high-density concrete.
The ball is the same size and weight as a regulation NFL ball, but the AFL's balls are gold instead of brown. There has to be a good joke in there somewhere.
Eight players on the field per team, three players less than conventional football, even if you're one of those people who considers soccer "conventional football."
Four offensive players and three defensive players must line up on the line of scrimmage.
One receiver can be in forward motion when the ball is snapped; this is not considered offsides, so quit yelling for a flag, already.
Four 15-minute quarters, just like God intended. Overtime is 15 minutes also, but each team gets one possession to score before sudden death begins.
Rules and Scoring
The clock is stopped each half for the "one-minute warning." Incomplete passes or out-of-bounds plays (the ball carrier can hold the ball over the wall to "run out of bounds") only stop the clock in the last minute of the half.
Each team gets three time-outs per half and zero challenges.
The offense still gets four downs to move the ball 10 yards, because two downs to get five yards would be ridiculous.
Scoring is mostly the same, but a successful drop kick earns two points on the extra point and four points as a field goal. This distinction isn't all that important because nobody drop kicks in the AFL.
Receivers must have one foot in-bounds for a complete pass. Considering the out-of-bounds line is a 4-foot wall, players still try pretty hard to land with both feet in bounds.
Kickoff is from the goal line and is often caught off the net. A touchback is put on the receiving team's 5-yard line. Punting is illegal and would probably look pretty lame on a 50-yard field.