Deadweight Tonnage (DWT)
The total weight a ship can carry (cargo plus fuel, stores, crew and water) at her load line, in metric tonnes.
- Category
- Vessel Size and Tonnage
- Abbreviation
- DWT
- Dictionary entry
- Deadweight Tonnage
- Last reviewed
How it works
Deadweight tonnage (DWT) is the carrying capacity of a vessel: the difference between her loaded and light displacement, expressed in tonnes. It includes cargo, bunkers, fresh water, stores, ballast and crew: everything the ship can take on before reaching her maximum permitted draught.
DWT is the headline size measure for bulk carriers and tankers and the basis for most freight, valuation and segment comparisons, because it approximates how much revenue cargo a ship can lift. It differs from gross tonnage, which measures enclosed volume, not weight.
Where it shows up on The Maritime
Also known as: DWT, deadweight, deadweight tonnes.
The short dictionary definition is at Dictionary entry: Deadweight Tonnage. This page is the explainer.
Related terms
Gross Tonnage (GT)
A dimensionless measure of a ship’s total internal volume, used for regulation, manning and port-due calculations.
Draught
The vertical distance from the waterline to the bottom of the keel: how deep the ship sits in the water.
Ballast
Seawater carried in tanks to keep an unladen ship stable and properly trimmed; also the term for a non-revenue, empty leg.
Kamsarmax
A dry-bulk carrier sized to the maximum length that can load at the port of Kamsar in Guinea, one step above the classic Panamax.
Very Large Crude Carrier (VLCC)
A crude oil tanker in the largest actively traded class: the backbone of long-haul Middle East to Asia oil transport.
More vessel size and tonnage terms
A plain-English reference definition: our own explanation of a standard shipping concept, not a licensed source or legal advice. See the full glossary or the broader maritime dictionary.
Last reviewed: .