Hash marks

Hash marks are short lines, running perpendicular to sidelines or sideboards, used to mark locations, primarily in sports.

In ice hockey, the hash marks are two pairs of parallel lines on either side of the face-off circles in both ends of the rink. Players must remain on their team's side of the hash mark nearest their own goal during a face-off until the puck hits the ice.

In US football and Canadian football, the hash marks are two rows of lines near the middle of the field that are perpendicular to the side lines. These small lines (about 1 yard long) are used to mark each of the 5-yard lines, which go from sideline to sideline. All plays start with the ball on or between the hash marks. That is, if the ball is downed in between a hash mark and the nearest sideline, it must be reset on the hash mark for the next play. The width of a standard football field in the United States is 160 feet (53⅓ yards).

Prior to the adoption of hash marks (which were first utilized at the first NFL playoff game in 1932), all plays began where the ball was declared dead, including extra point attempts.

The hashmarks in that indoor 1932 playoff game were originally 10 yards from the sideline, and that width was adopted by the NFL for the 1933 season. It was increased to 15 yards (70 feet apart) in 1935, 20 yards (40 ft apart) in 1945, and to the current 23 yards, 1 foot, 9 inches (18½ ft apart) in 1972.

In most forms of professional football in the U.S., including the National Football League and most forms of indoor football, the hash marks are in line with the goal posts, both being 18 feet 6 inches apart. High school football, college football and Canadian football have hash marks significantly wider than the goal posts. The college football standard, which was the previous standard in the NFL (1945–1971), is 40 feet apart, (20 yards from the sidelines) introduced in 1993. Previously, the college width was the same as the high school standard, at one-third of the width of the field (53⅓ feet).

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