The freeboard of a ship is distance between the water level and the upper surface of the deck amidships.

A ship with low freeboard will have water coming onto the deck in most sea states. If the ship is not water-tight then there is risk of taking on water and sinking.


A ship with high freeboard has a deck free of water in most sea states. However, the ship's center of gravity may be high, making the ship unstable. A ship with a high free board has more space for cargo or accommodations.


Factors affecting the freeboard:

(1) ship design

(2) load onboard (the higher the weight the lower the freeboard)

(3) mishap pulling the ship down


A ship may have load lines on the hull, indicating how low the ship is in the water.

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