TEU

A TEU (Twenty-foot Equivalent Unit) is the standard unit of measurement for container capacity in ocean shipping. One TEU represents the volume of a standard 20-foot intermodal shipping container (20 feet long × 8 feet wide × 8.5 feet tall, approximately 33 cubic meters or 1,172 cubic feet of usable space). It is the universal currency of container shipping — used to measure vessel capacity, port throughput, terminal operations, and trade volumes.

Origins of the TEU

The TEU standard emerged alongside containerization in the 1960s. When Malcolm McLean pioneered intermodal container shipping with the Ideal X in 1956, he used a 35-foot container. The industry converged on the 20-foot standard as a balance between cargo capacity and the ability to handle containers efficiently at ports with the cranes and equipment of the era.

Today the dominant container in use is actually the 40-foot container (2 TEU), which offers the same port handling complexity but double the cargo capacity per lift. The majority of ocean freight moves in 40-foot containers; 20-foot containers are used primarily for heavy, dense cargo that would exceed the weight limit of a 40-footer if fully loaded.

Container Sizes and TEU Equivalents

Vessel Capacities

Container ship sizes are measured in TEUs:

• Feeder vessels: 300–2,000 TEU — serve smaller ports and short-sea routes
• Regional vessels: 2,000–6,000 TEU — intra-Asia, trans-Atlantic, Latin America
• Post-Panamax: 6,000–12,000 TEU — named for the original Panama Canal's maximum lock size (13,000 TEU)
• New Panamax: 12,000–15,000 TEU — fit through the expanded Panama Canal (opened 2016)
• Ultra Large Container Vessels (ULCVs): 18,000–24,000 TEU — the largest ships on Earth, used on Asia-Europe routes

The MSC Irina, launched in 2023, is the world's largest container ship at 24,346 TEU — nearly 400 meters long, carrying goods equivalent to roughly 24,000 20-foot containers.

Port TEU Throughput

The world's busiest container ports, ranked by annual TEU throughput:

1. Shanghai: ~50 million TEU/year
2. Singapore: ~39 million TEU/year
3. Ningbo-Zhoushan: ~37 million TEU/year
4. Shenzhen: ~30 million TEU/year
5. Guangzhou: ~25 million TEU/year
6. Busan: ~23 million TEU/year
7. Hong Kong: ~17 million TEU/year
8. Qingdao: ~26 million TEU/year

US ports are considerably smaller by comparison: Los Angeles/Long Beach combined handle approximately 17–18 million TEU/year, making them 6th–7th globally.