Tankers get sized the same way bulk carriers and container ships do — by the ports, canals and routes they need to fit through, not by round numbers. The result is a handful of named classes that every broker, charterer and terminal uses as shorthand: MR, LR1, LR2, Aframax, Suezmax, VLCC. Get the class right and you’re buying a ship that fits your trade; get it wrong and you own tonnage that can’t reach the terminals or carry the cargo you actually need. This explainer covers what each class means, for anyone comparing against our product tanker or chemical tanker buyer’s guides.
Tanker size classes — by deadweight
| Class | Indicative DWT | Typical cargo & role |
|---|---|---|
| MR (Medium Range) | ~25,000–54,999 DWT | Clean petroleum products and chemicals; the most numerous and flexible tanker size, fits the widest range of ports |
| LR1 (Panamax) | ~55,000–79,999 DWT | Longer-haul clean and dirty products, sized to transit the Panama Canal |
| LR2 / Aframax | ~80,000–119,999 DWT | Crude and dirty products (Aframax) or long-haul clean products (LR2) — same hull size, different service; the world’s most widely used crude-capable size |
| Suezmax | ~120,000–199,999 DWT | Crude oil, sized to transit the Suez Canal laden — the largest tanker that can |
| VLCC (Very Large Crude Carrier) | ~200,000–319,999 DWT | Long-haul crude between major load and discharge terminals; too large for most berths, often works via single-point moorings or ship-to-ship transfer |
A handful of ULCCs (Ultra Large Crude Carriers, 320,000+ DWT) still trade, but new tonnage in that band has been rare for decades — VLCC is effectively the practical ceiling for most crude trades today.
Product tanker vs. crude tanker — same hull sizes, different service
MR, LR1 and LR2 are product-tanker classes; Aframax, Suezmax and VLCC are crude classes — but the size bands overlap (LR2 and Aframax are the same DWT range) because what actually separates a product tanker from a crude tanker isn’t the hull, it’s the cargo system:
- Coated vs. uncoated tanks — product tankers carry epoxy- or zinc-coated tanks to keep refined products clean and prevent corrosion; crude tankers typically run uncoated.
- Segregation — product tankers usually carry multiple independent cargo lines and pumps so several different grades can be loaded and discharged without contamination; crude tankers need far less segregation.
- Cargo heating — some products and most crude grades need heating coils to keep viscous cargo pumpable; the fit-out differs by trade.
See our chemical tanker guide for the more demanding IMO Type 1/2/3 segregation and stainless-steel tank requirements that sit a step beyond standard product-tanker coating.
Tip: Don’t shop by DWT alone. An Aframax and an LR2 can be the identical hull size, but one is fitted for crude and the other for clean products — check the tank coating and cargo-line segregation before you check the deadweight, or you’ll buy a ship that can’t lift the cargo you actually trade.
Why the size band matters for a buyer
The class name is really a proxy for three practical constraints:
- Port and canal draft — Suezmax and VLCC exist because of the Suez Canal’s laden-transit limit; LR1 tracks the Panama Canal. Buy above your trade’s real port depth and you’re paying for capacity you can’t use.
- Terminal access — plenty of terminals simply can’t berth a VLCC; that tonnage works through offshore transfer (SPM, ship-to-ship) rather than alongside, which changes your operating cost and flexibility.
- Charter market liquidity — MR and Aframax are the most heavily traded, most liquid size bands, which tends to mean tighter buy/sell spreads and an easier resale than a less common class.
What this means for a tanker buyer in 2026
Start from your trade, not the biggest ship your budget allows. Match the size class to the ports and canals you actually call, decide product vs. crude service before you decide DWT, and remember that LR2 and Aframax buyers are shopping the same hull for two different jobs — the cargo system, not the tonnage figure, is what makes the ship right or wrong for you. See our product tanker and chemical tanker buyer’s guides for what to check on a specific candidate, read the current product tanker and chemical tanker market reports, or talk to a broker about a specific opportunity.