How do you calculate naval tonnage?

Naval tonnage is typically calculated using the volume of a ship's hull, measured in cubic feet or meters, and then converted to tonnage by dividing by a standard density, usually around 35 cubic feet per ton for seawater. The most common methods include Gross Tonnage (GT), which measures the total internal volume, and Net Tonnage (NT), which accounts for usable space after excluding non-revenue generating areas. Tonnage can also be expressed in terms of displacement, which refers to the weight of the water displaced by the ship when floating. The specific formula and method can vary depending on the purpose and regulatory requirements.