According to Rule 2 of the 2011 Official Playing Rules and Casebook of the National Football League, an official NFL ball must meet the following requirements:

• The ball must be a “Wilson,” hand selected, bearing the signature of the Commissioner of the League.
• The ball shall be made up of an inflated (12 ½ to 13 ½ pounds) urethane bladder enclosed in a pebble-grained leather case (natural tan color) without corrugations of any kind.
• It shall have the form of a prolate spheroid and the size and weight shall be: long axis, 11 to 11 ¼ inches; long circumference, 28 to 28 ½ inches; short circumference, 21 to 21 ¼ inches; weight, 14 to 15 ounces.

If an NFL football must have such large dimensions, just how big is a football player’s hand span?

Hand span is the distance between your pinky finger and thumb when your hand is stretched as far as it will go. To measure hand span, place your outstretched hand, palm down, on top of a ruler. The tip of your pinky finger should be at the first mark on the ruler. The distance between the outside tip of your pinky finger and the outside tip of your thumb is your hand span.