deadweight

ship design

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June 25, 2026

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Deadweight refers to a ship's carrying capacity, encompassing the total weight of cargo, fuel, stores, crew, and passengers. It is calculated as the difference between a ship's fully loaded displacement and its light displacement. This measurement is often expressed in deadweight tons, with one deadweight ton equaling a long ton.123

In ship design, deadweight is a crucial factor. Naval architects must balance the deadweight a ship is designed to carry with the ship's lightship weight (structure, machinery, etc.) to determine the total displacement required for the vessel to float safely. This calculation is fundamental to naval architecture, ensuring the ship displaces a weight of water equal to its own total weight.45

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ship
Hydrostatics
…form a total known as deadweight. To deadweight must be added the weight of the ship’s structure, propulsion machinery, hull engineering (nonpropulsive machinery), and outfit (fixed items having to do with crew life support). These categories of weight are known collectively as lightship weight. The sum of deadweight and lightship…
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…form a total known as deadweight. To deadweight must be added the weight of the ship’s structure, propulsion machinery, hull engineering (nonpropulsive machinery), and outfit (fixed items having to do with crew life support). These categories of weight are known collectively as lightship weight. The sum of deadweight and lightship…
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tanker
(Deadweight is the total weight of cargo plus such necessary supplies as fuel, lubricating oil, crew, and the crew’s life support.) Between these two extremes are various size classes, though the exact specifications for each class vary among sources. Common tanker designations, in descending order…
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(Deadweight is the total weight of cargo plus such necessary supplies as fuel, lubricating oil, crew, and the crew’s life support.) Between these two extremes are various size classes, though the exact specifications for each class vary among sources. Common tanker designations, in descending order…
Read More