What is the center of buoyancy?

The center of buoyancy is the point at the center of the volume of fluid displaced by a vessel. It relates to the center of gravity, but it is not the same point. If a ship is upright, its center of buoyancy is located directly below the center of gravity.

For a vessel of uniform construction, such as a wood block, the center of gravity is at the geometric center. When the block floats in water, the center of buoyancy is at the geometric center of the part of the block that is under water. Since ships are not of uniform construction, their designs and the distribution of their loads affect both their centers of gravity and the centers of buoyancy.