About 60% of the world's oil travels by sea. The ships range from half-million-barrel Aframaxes to 2-million-barrel VLCCs, freight adds only dollars per barrel — until it doesn't — and a sanctions-era "shadow fleet" now moves a growing share in the dark. Live positions on the tanker map.
| Class | Cargo | Size | Typical role |
|---|---|---|---|
| Panamax | ≈350–500k bbl | ≈50–80k DWT | Sized for the old Panama Canal locks; products and short-haul crude |
| Aframax | ≈500–800k bbl | ≈80–120k DWT | Workhorse of regional trades (Baltic, Med, US Gulf exports) |
| Suezmax | ≈800k–1M bbl | ≈120–200k DWT | Largest able to transit the Suez Canal fully laden |
| VLCC | ≈2M bbl | ≈200–320k DWT | Very Large Crude Carrier — the standard long-haul ship (Mideast→Asia) |
| ULCC | ≈3M+ bbl | ≈320k+ DWT | Ultra Large — a handful exist; too big for most ports, mostly used for storage |
DWT = deadweight tonnes. Related: the Strait of Hormuz · biggest oil spills · Russia's shadow fleet · live tanker map.
A VLCC — the standard long-haul crude carrier — holds about 2 million barrels, roughly $160 million of cargo at $80 oil, and enough to supply the entire UK for a day and a half. Smaller Aframax ships carry ~600,000 barrels on regional routes.
Remarkably little in normal times: moving a barrel from the Middle East to Asia on a VLCC typically costs $1–3 — a couple of percent of the cargo value. Rates are wildly volatile though: in tight markets or war scares, daily charter rates have jumped from $20,000 to over $200,000, briefly adding $10+ per barrel on some routes.
Several hundred mostly older tankers that operate outside Western insurance, flagging and finance so they can carry sanctioned Russian, Iranian and Venezuelan crude. They routinely disable AIS transponders and transfer cargo ship-to-ship at sea — raising spill risk, since these are aging ships with opaque ownership and questionable maintenance.
Yes — commercial AIS networks show most of the world fleet in real time (our tanker map embeds one, centered on the Strait of Hormuz). Caveats: "destination" fields are typed by crews and unreliable, and shadow-fleet vessels deliberately go dark, which is itself a signal analysts watch.