Dry bulk

Capesize
Roughly 100,000–210,000 dwt. Too large for the Panama Canal in its historic form, hence the name. Carries iron ore and coal on long-haul routes such as Brazil and West Australia to China.
Newcastlemax
About 205,000 dwt, the largest bulker able to berth at Newcastle, Australia. Traded as a premium Capesize.
Kamsarmax
About 82,000 dwt, the largest bulker able to load at Port Kamsar, Guinea. The dominant modern Panamax design.
Panamax
Roughly 65,000–82,000 dwt. Workhorse of the coal and grain trades, sized to the original Panama Canal locks.
Supramax / Ultramax
Roughly 50,000–65,000 dwt with onboard cranes, allowing calls at ports without shore gear. Carries minor bulks, grain, steels and fertilisers.
Handysize
Roughly 10,000–40,000 dwt, geared and highly flexible, serving smaller ports and parcel-sized cargoes.

Tankers

VLCC
Very Large Crude Carrier, about 2 million barrels of crude. The benchmark for Middle East Gulf to Asia crude voyages.
ULCC
Ultra Large Crude Carrier, above 320,000 dwt. A small and shrinking class, sometimes used for floating storage.
Suezmax
About 1 million barrels, sized to transit the Suez Canal laden. Common on West Africa and Black Sea crude runs.
Aframax
About 750,000 barrels, the standard for shorter-haul crude trades in the North Sea, Mediterranean and Caribbean.
LR1 / LR2
Long Range product tankers on Panamax and Aframax hulls, moving clean products such as jet, gasoil and naphtha over long distances.
MR
Medium Range product tanker of roughly 45,000–55,000 dwt, the backbone of regional clean product arbitrage.
LNG carrier
Purpose-built gas carrier moving liquefied natural gas at around minus 162C, typically 145,000–174,000 cubic metres.
VLGC
Very Large Gas Carrier for LPG and ammonia, typically around 84,000 cubic metres.

Container ships

ULCV
Ultra Large Container Vessel above roughly 18,000 TEU, deployed almost exclusively on Asia–Europe headhaul services.
Neo-Panamax
Sized to the expanded Panama Canal locks, roughly 12,000–15,000 TEU, used on Asia–US East Coast services.
Panamax boxship
Older generation up to about 5,000 TEU, now largely cascaded to regional and north–south trades.
Feeder
Under about 3,000 TEU, connecting hub ports to smaller regional terminals.
TEU
Twenty-foot Equivalent Unit, the standard measure of container capacity and volume.

Follow the tonnage: bulk carriers, tankers and container ships. For how these classes are priced, read the freight rates guide and the Baltic Dry Index guide.