A surfboard is traditionally classified as a longboard when it is at least nine feet long.
Longboards are larger, wider, and generally more stable than shortboards. Their extra volume makes it easier to catch smaller or slower waves, and their length supports classic maneuvers such as walking toward the nose and “hanging ten.” The nine-foot benchmark is a widely used traditional distinction rather than an absolute rule in every modern board-design context.
Longboarding developed from the large wooden boards used in Polynesian and Hawaiian surfing. During the mid-20th century, lighter foam-and-fiberglass construction allowed boards to become shorter and more maneuverable, leading to the rise of the shortboard revolution in the late 1960s.
Some boards near the boundary are described as “funboards” or “midlengths.” Those labels reflect design and riding style, so length alone does not capture every category used by surfboard makers.