Deadweight TonnageDWT
The total weight a ship can carry — cargo plus fuel, stores, crew and water — at her load line, in metric tonnes.
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.
On TheMaritime
Also known as: deadweight, deadweight tonnes, DWT.
Related terms
Gross TonnageGT
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 — and the term for a non-revenue, empty leg.
Kamsarmax
A dry-bulk carrier of about 80,000–85,000 DWT, sized to the maximum length that can load at the port of Kamsar in Guinea.
Very Large Crude CarrierVLCC
A crude oil tanker of roughly 200,000–320,000 DWT — the backbone of long-haul Middle East–to–Asia oil transport.
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: June 2026.