Kites come in sizes ranging from 0.7 square meters to 21 square meters, or even larger. In general, the larger the surface area, the more power the kite has, although kite power is also directly linked to speed, and smaller kites can be flown faster; a tapering curve results, where going to a larger kite to reach lower wind ranges becomes futile at a wind speed of around eight knots. Kites come in a variety of designs. Some kites are more rectangular in shape; others have more tapered ends; each design determines the kites flying characteristics. 'Aspect ratio' is the ratio of span to length. Wider shorter (ribbon-like) kites have less drag because the wing-tip vortices are smaller. High aspect ratios (ribbon-like kites) develop more power in lower wind speeds.

Seasoned kiteboarders will likely have three or more kite sizes which are needed to accommodate various wind levels, although bow kites may change this, as they present an enormous wind range; some advanced kiters use only one bow kite. Smaller kites are used by light riders, or in strong wind conditions; larger kites are used by heavier riders or in light wind conditions. Larger and smaller kiteboards have the same effect: with more available power a given rider can ride a smaller board. In general, however, most kiteboarders only need one board and one to three kites (7-12m in size). (source Wikipedia)