Insights · Ship identity · Ship types
Almost every commercial ship is defined by one thing: what it was built to carry. Sort the world fleet by cargo and the bewildering variety resolves into a handful of clear families — and that is exactly how the Marifest registry groups it.
Stand on a quay in Rotterdam and the ships passing look endlessly varied. They are not. Almost every commercial vessel belongs to one of about nine families, and a ship's family is decided by a single question: what does it carry? A tanker is built around liquid cargo, a bulker around loose dry cargo, a boxship around standardised steel containers. Once you read a ship by its cargo, its hull form, its deck layout and even its profile on the horizon start to make sense. This is also how the Marifest registry sorts the fleet — by sector — so you can list every vessel of a kind in one query.
Bulk carriers move unpackaged dry cargo poured loose into the hold: iron ore, coal, grain, bauxite, cement. You recognise them by a long flush deck punctuated by box-shaped hatch covers over a row of large cargo holds. They are sized into well-known classes — Handysize, Handymax/Supramax, Panamax (the largest that fit the old Panama Canal locks), Kamsarmax, and Capesize, the giants too big for either canal that must route round the Cape of Good Hope or Cape Horn. Together with tankers they form the great workhorse fleets of world trade.
Tankers carry liquids in a set of internal tanks. The family splits by what is inside: crude-oil tankers, product (clean and dirty) tankers carrying refined fuels, and chemical tankers with coated or stainless tanks for aggressive cargoes. Crude tankers are sized as Aframax, Suezmax (the largest that transit the Suez Canal laden), VLCC (Very Large Crude Carrier, roughly 180,000–320,000 deadweight tonnes) and ULCC. Tankers dominate sanctions and compliance work, because crude and products are the cargoes most often moved by the so-called shadow fleet. To list them, filter the registry with /ships?sector=tanker.
Container ships — boxships — carry standardised intermodal containers, measured in twenty-foot equivalent units (TEU). They are the backbone of manufactured-goods trade, stacking containers in cell guides below deck and in towering tiers above. The largest Ultra Large Container Vessels now exceed 24,000 TEU. Their size is described directly in TEU rather than tonnage, which is why tonnage figures can mislead on a boxship.
Gas carriers move cargo that must be kept liquefied under cold, pressure or both. LNG carriers transport liquefied natural gas at around −162°C in distinctive spherical (Moss) or membrane tanks; LPG carriers move propane, butane and ammonia. They are among the most technically demanding and valuable ships afloat, and a growing share of new tonnage as gas trades expand.
Two more families round out dry trades. General-cargo ships (including multi-purpose and project-cargo vessels) carry mixed, often break-bulk cargo with their own cranes, serving ports without container infrastructure. Ro-ro ("roll-on/roll-off") vessels and pure car and truck carriers (PCTCs) carry wheeled cargo driven on and off through stern or side ramps — the tall, slab-sided ships that move new vehicles by the thousand.
Passenger ships carry people rather than cargo. They range from ferries and ro-pax vessels on fixed routes to the vast cruise ships that are effectively floating resorts. Because of the lives aboard, passenger ships face the strictest safety regime under SOLAS. The major operators behind them are profiled on Marifest's cruise lines pages.
The offshore family supports energy at sea: platform supply vessels (PSVs), anchor-handling tug supply (AHTS) ships, dive-support, cable-lay and the crew-transfer and service vessels now built for offshore wind. Add the harbour fleet — tugs, dredgers, pilot boats — and you have the vessels that keep ports and energy infrastructure working.
Fishing vessels are a class apart: trawlers, purse-seiners, longliners and factory ships. They are often exempt from the IMO number scheme in some jurisdictions, which complicates identification, yet they matter for compliance because illegal, unreported and unregulated (IUU) fishing and at-sea transhipment draw growing regulatory attention.
Read a ship by its cargo and everything else follows — the hull form, the deck layout, the size class, even the rules it must obey. How the Marifest registry sorts the fleet
Knowing the type is the start of reading a vessel, but it is rarely the end of the question. Once you have placed a ship in its family you usually want the specifics — its flag, its owner, its sanctions standing — or you want to see the whole sector at once on the live map. Marifest lets you do both across 97,000+ vessels: filter by sector, then open any file. Unfamiliar terms along the way are defined in the maritime glossary.
How Marifest uses it
Marifest groups every vessel by sector, so you can move from the whole tanker fleet to a single hull in two clicks — and read its specs, owner, flag and sanctions standing on one screen.
List every ship of a type with a single query — /ships?sector=tanker, =bulker, =container or =cruise — across 97,000+ vessels.
Each file shows the figures that matter for its family: deadweight for a bulker, TEU for a boxship, gross tonnage for a cruise ship.
Passenger and cruise tonnage links to the operators behind it on the dedicated cruise lines pages.
Because tankers carry the cargoes most exposed to sanctions, every tanker file is keyed to its IMO number for clean compliance screening.