Deadweight tonnage

What is Deadweight Tonnage?

Deadweight tonnage (DWT) is a measure of a ship's carrying capacity, representing the total weight of cargo, fuel, crew, provisions, and other materials that the vessel can safely carry. It is expressed in tons and includes everything that adds weight to the ship, except for the vessel’s own weight. DWT is crucial for understanding a ship's cargo capacity and operational limits, as it helps in planning voyages and managing cargo efficiently.

How is Deadweight Tonnage Calculated?

Deadweight tonnage is calculated by finding the difference between a ship’s fully loaded weight and its empty weight. To do this, you first determine the weight of the ship when it is fully loaded with cargo, fuel, and supplies. Then, subtract the ship's weight when it is empty (known as the lightweight). The result is the deadweight tonnage, which represents the total weight the ship can carry.

Deadweight Tonnage = (Fully loaded weight - Lightweight)

This measure provides a clear picture of the ship's cargo carrying capacity and helps in optimizing loading and operational planning.

Difference Between Gross Tonnage and Deadweight

Gross tonnage (GT) and deadweight tonnage (DWT) are distinct metrics used to measure different aspects of a ship.

‍Gross tonnage refers to the total internal volume of a ship, including all enclosed spaces, and is used for regulatory, safety, and port fees purposes. It is a measure of the ship's overall size and internal capacity.

Deadweight tonnage, on the other hand, measures the weight capacity of a ship, including cargo, fuel, and other loads.

While gross tonnage assesses the ship's internal volume, deadweight focuses on its carrying capacity and operational load.