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# How do get get the net tonnage of a vessel by its dead weight tonnage?

You can't get it directly, as one is a measure of volume and the other of mass..
Net Tonnage is a measure of volume of a ship, more precisely the volume of a ship that's usef…ul for carrying cargo and passengers. So, essentially you take the internal volume of the ship and remove the volume of the fuel, engine spaces, crew quarters and so on. 100 cubic feet is the volume used for calculating net and gross registered (GRT) tonnage of a ship..
Dead weight tonnage is the actual weight of what a ship can carry. To get this, you take the displacement of a fully loaded ship and then subtract from that the displacement of it when totally empty. And since displacement is actually the amount of water displaced by a vessel, it corresponds to the actual weight of the ship. (MORE)