In international shipping, understanding how container capacity is measured is essential to accurately plan cargoes, calculate costs and compare quotes. Among all the units used in the industry, the TEU (Twenty-foot Equivalent Unit) and FEU (Forty-foot Equivalent Unit) have become the global standards for representing the space available on vessels, terminals and logistics services.
These units allow companies to speak the same operational language, simplifying space reservation, rate estimation and volume planning.
For companies that import or export goods on a regular basis, understanding what a TEU or FEU really means is key to optimizing their logistics strategy and making informed decisions.
In this article we explain in a clear way what TEU and FEU are, how they differ and how they influence the maritime transport management.
What is a TEU and what is it used for in international logistics?
The TEU (Twenty-foot Equivalent Unit) is the standard unit used in shipping to measure the equivalent cargo capacity of a 20-foot container.
It does not represent a physical container per se, but a unit of measurement that allows the comparison, planning and calculation of space in ships, terminals and logistics operations.
Its use makes it easier for shipping companies, freight forwarders importers and exporters to work with the same operating language. Thanks to the TEU, it is possible to know quickly:
🚢 The total capacity of a vessel.
🏗️ The space available at a port terminal.
📦 The approximate volume that a load will occupy.
💸 The rates applied for containers and maritime services.
For example, if a vessel has a capacity of 18,000 TEUs, it means that, in theory, it can carry 18,000 20-foot containers or 9,000 40-foot containers, or any equivalent combination.
How TEU capacity is measured: vessels, terminals and tariffs
The TEU is used at different levels of the maritime chain:
Container ships: their size is expressed in TEU to facilitate comparisons between shipping lines and routes.
Port terminals: handling and storage capacity is also measured in TEUs to plan inbound and outbound flows.
Freight rates: many rates are structured on a TEU basis, whether for freight, storage, port movement (THC) or surcharges.
This standardization makes it possible to coordinate all shipping players under the same metric, reducing errors and facilitating planning.
Practical examples to understand how many TEUs a cargo requires
Understanding TEU is especially useful for companies that must plan for recurring exports or imports. Some examples:
One 20-foot container = 1 TEU
One 40-foot container = 2 TEU
One High Cube container (40HC) = 2 TEU
Two 20-foot containers are equivalent to a single 40-foot container in terms of TEU (2 TEU in both cases), although their interior capacity varies.
In practice, this equivalence helps to decide which type of container is most suitable for each commodity, taking into account space, weight and cost.
What is an FEU and how does it relate to the TEU?
The FEU (Forty-foot Equivalent Unit) is the equivalent unit of a 40-foot container. Unlike the TEU, which represents a standard 20-foot container, the FEU is used to measure larger volume cargoes or for operations where a single large container is more efficient than two smaller ones.
In terms of equivalence, 1 FEU = 2 TEU, since a 40-foot container is twice the length of a 20-foot container. This ratio makes it easy to understand how to calculate vessel capacity, terminal availability or the cost of a shipment.
The use of the FEU is especially common on international routes with large volumes of cargo, where optimizing interior space and reducing handling is a key factor for agile and cost-effective operations.
Operational differences between using TEU and FEU
Although one FEU is equivalent to two TEUs in terms of standardized capacity, it is not always the same to use one or the other in practice. The main operational differences are:
Maneuverability: 20-foot containers are more maneuverable and, in some countries, allow more weight to be transported.
Useful volume: a 40-foot container offers greater cubic capacity, making it ideal for bulky or light goods.
Cost per unit of cargo: on many routes, one FEU is often cheaper than two TEUs, which can generate savings.
Availability: depending on the region or season, there may be a greater supply of 20 feet or 40 feet, influencing planning.
These differences make the choice between TEU or FEU depend on both the type of cargo and the company’s operational objectives.
When to choose 20′ or 40′ containers depending on the load
Choosing the right container is key to optimize space, costs and time. In general:
20 ft (1 TEU): Ideal for heavy and compact cargoes, where the total weight is reached before the volume (chemicals, metal, machinery, dense materials).
40 feet or 40HC (1 FEU = 2 TEU): Recommended for bulky or light goods, where the limitation is usually interior space and not weight (textile, plastic, electronics, consumer goods).
Mixed or palletized loads: They usually make better use of the FEU due to its greater cubic capacity and reduced handling.
In short, the relationship between TEU and FEU is not only a matter of measurement, but a strategic logistical decision.
Related content:
👉🔗 Containers for maritime transport. Types and Characteristics
👉🔗 Shipping Container Dimensions. Measurements and specifications
👉🔗 How many pallets fit in a 20′ and 40′ container. [+Infographic]
Why it is important to know these units if you manage logistics operations
Understanding what TEU and FEU really mean is essential for any professional involved in import, export or logistics planning processes.
These units are not only used to measure containers: they also influence cost, space occupancy, transport planning and quotation interpretation.
Mastering its use allows more accurate decisions to be made, frequent errors to be avoided and the resources available in the supply chain to be optimized.
Impact on load planning and space occupancy
Knowing how many TEUs or FEUs an operation requires allows:
📏 Determine the most suitable type of container according to volume and weight.
🔢 Calculate how many units a full (FCL) or shared (LCL) load will require.
🏢 Provide for the occupation of warehouses, terminals or depots.
📦 Identify whether it is possible to consolidate merchandise to optimize space.
Working with standardized units makes planning clearer, comparable and more efficient.
How they affect transportation costs and volume/weight tariffs
Ocean rates are often calculated on a space basis in TEU or FEU, so these units directly influence the final budget. Knowing how to interpret them helps:
⚖️ Compare rates between different shipping lines or freight forwarders.
📐 Understand whether it is more cost effective to ship 2×20′ (2 TEU) or 1×40′ (1 FEU = 2 TEU).
🧮 Assess weight, volume or port surcharges.
💡 Detect savings opportunities by consolidating or reconfiguring the load.
On many routes, one 40-foot container can be more economical than two 20-foot containers, something that can only be understood by mastering these metrics.
Interpretation of quotations, contracts and shipping documents
In the maritime documentation, from quotations to BLs bookings or contracts of carriage, references to TEU and FEU are constant. Understanding them allows:
❗ Avoid misunderstandings about the contracted space.
💼 Correctly review rates and surcharges.
Identify whether a price is calculated per container, per unit or per TEU equivalent.
🤝 Align expectations between logistics, operations and commercial teams.
In short, the operational knowledge of these units contributes to reducing errors, streamlining processes and improving the economic and physical traceability of each shipment.
Common mistakes when interpreting TEU and FEU and how to avoid them
Although TEU and FEU are widely used units in maritime transport, their interpretation can generate confusion, especially when concepts such as volume, useful capacity or costs per container are mixed. These errors can affect planning, budgeting and day-to-day operations.
Here are the most common pitfalls and how to avoid them to ensure more accurate logistics management.
Confusing volume with physical units
One of the most common mistakes is to assume that a TEU represents a physical container.
In fact:
📘 1 TEU = unit of measurement, not an actual container.
📘 A 10,000 TEU capacity vessel does not carry exactly 10,000 20-foot containers.
📘 One FEU (40 feet) occupies 2 TEU, but is still a single container.
How to avoid it: Always distinguish between equivalent size (TEU/FEU) and physical container (20′, 40′, 40HC). This avoids confusion when interpreting vessel capacities, rates or terminals.
Failure to consider useful capacity vs. theoretical capacity
Not all containers can be filled to 100%. Actual capacity depends on:
⚖️ The maximum weight allowed per country or shipping line.
📦 The type of goods (bulky vs. heavy).
🧩 The internal distribution of the product.
🛠️ Handling or stowage restrictions.
For example, a 20′ can carry more weight than a 40′, but has less usable volume. Conversely, a 40HC has more space, but cannot always be loaded to its maximum due to weight limitations.
How to avoid it: Always work with useful capacity (volume + admissible weight) and not only with the theoretical value of the container.
Lack of alignment between logistics and commercial team in estimations
Another common problem is the lack of coordination between those who calculate space and those who negotiate rates or prepare budgets. This may cause:
📏 Overestimation or underestimation of space required.
🔄 Wrong choice between 20′ and 40′.
🧾 Quotes that do not match the actual cargo volume.
💸 Increased costs due to poorly based decisions.
How to avoid it: Establish a clear flow between logistics, operations and commercial, where all work with the same units, equivalences and capacity criteria.
Across Logistics, your partner in ocean freight and global logistics planning
Managing maritime operations with precision requires more than knowing units such as TEU or FEU: it means having a partner capable of offering reliable, transparent and tailored solutions for each type of cargo.
At Across Logistics we work with a consolidated international network and a team specialized in maritime transport, customs and integrated logistics.
We accompany companies importing and exporting goods to multiple markets, offering FCL and LCL ocean freight, container space planning, route optimization and support in all the necessary documentation for each shipment.
If you need to improve the efficiency of your operations or resolve doubts about your cargo planning, we are here to help you.
Talk to our team and find out how to optimize your maritime logistics with a reliable partner.
