Feeder → Panamax → ULCV
Container Ship Sizes
Ship classes are named after the waterways that constrain them. The original Panama locks capped ships at 32.31 m of beam — “Panamax”, about 5,100 TEU. The 2016 expansion created “Neo-Panamax” at 51.25 m and ~14,000–15,000 TEU. Beyond canals, only ports limit size: today’s largest vessels stack containers 24 wide and 12 high above deck.
Size classes
| Class | Capacity | Dimensions | Draft |
|---|---|---|---|
| Feeder | ≤3,000 TEU | ~200 m | — |
| Panamax | ~5,100 TEU | 294 × 32.3 m | 12 m |
| Neo-Panamax | 14–15,000 TEU | 366 × 51.25 m | 15.2 m |
| ULCV | 24,000+ TEU | ~400 × 61 m | ~16 m |
The next hard ceiling is “Malaccamax”: the Strait of Malacca’s ~25 m depth limits draft to about 20.5 m, capping any realistic Asia–Europe design near 30,000 TEU. For perspective: one 24,000 TEU vessel carries the cargo of roughly 12,000 trucks. Its deck area approaches four football pitches.
The record holders
MSC Irina and sisters (2023–) lead at 24,346 TEU. Close behind: OOCL Spain class (24,188), MSC Tessa class (24,116), Evergreen A-class (23,992). All are ~399–400 m long — length has plateaued; capacity growth now comes from width and stacking height.
How many containers actually fit
Nominal TEU assumes every slot filled with light boxes. Real loads run lower: weight limits, reefer plugs and stability rules mean a “24,000 TEU” ship typically sails with 18,000–19,000 TEU of actual cargo. About 1,000–1,500 containers are lost overboard per year across the entire ~250-million-move industry.
Frequently asked questions
What is the biggest container ship in the world?
The MSC Irina class leads at 24,346 TEU nominal capacity, about 399.9 m long and 61.3 m wide. Several classes from OOCL, MSC and Evergreen sit within a few hundred TEU of it.
How many containers fit on a cargo ship?
From a few hundred TEU on feeders to over 24,000 TEU on the largest vessels — nominally. Real-world loading is typically 75–80% of nominal because of weight and stability limits.
What does Panamax mean?
The maximum ship size that fits the original Panama Canal locks: 294.1 m length, 32.31 m beam — about 5,100 TEU. Neo-Panamax refers to the expanded 2016 locks: 366 m and 51.25 m beam.
How deep does a loaded container ship sit in the water?
Draft scales with size: Panamax ships draw up to 12 m, Neo-Panamax 15.2 m, and the largest ULCVs about 16 m fully loaded — which is why only a short list of deep-water ports can receive them.