A skipping rope should be between 7 feet 4 inches for a child and 9 feet 2 inches for an adult. These lengths are for ropes used by a single individual. Ropes that allow at least two people to jump should be 15 feet long.
When an individual jumps with the rope, there should be at least 12 inches of clearance between the head and the rope. One way to determine an appropriate length is to stand in the middle of the rope and pull up the ends. A properly sized rope should reach the armpits. When jumping with the rope, it should quickly brush the floor. A rope that solidly hits the floor is too long.