ISO 22T · 21,000–26,000 L
Tank Container Dimensions
A tank container is a stainless-steel pressure vessel inside a standard 20 ft ISO frame, moving liquids, gases and powders: chemicals, food-grade product, fuels. Because the frame matches a 20 ft dry box exactly (6.058 × 2.438 × 2.591 m), it rides any ship, chassis or railcar that takes a standard twenty.
Typical shells hold 21,000 to 26,000 litres. The practical limit is almost always weight: at 36,000 kg max gross for many tanks, a full 26,000 L shell of dense liquid hits the road weight limit before it hits the volume limit.
Against drums, the economics are lopsided: one 24,000 L tank replaces about 120 drums of 200 L each, loads and discharges by hose in an hour, and returns clean from a certified depot for the next product. That is why bulk liquid chemicals have moved almost entirely into ISO tanks.
Every tank carries a T-code and a data plate stating test pressure, capacity and permitted cargoes — the paperwork side of the type is as important as the steel, since the code determines which UN-numbered products the shell may legally carry.
| Metric | Imperial | |
|---|---|---|
| External dimensions | ||
| Length | 6.058 m | 19′11″ |
| Width | 2.438 m | 8′ |
| Height | 2.591 m | 8′6″ |
| Internal dimensions | ||
| Length | 6.058 m | 19′11″ |
| Width | 2.438 m | 8′ |
| Height | 2.591 m | 8′6″ |
| Specification | ||
| Tare weight * | 3,900 kg | 8,598 lb |
| Max gross weight | 36,000 kg | 79,366 lb |
| Max payload * | 32,100 kg | 70,768 lb |
| Capacity (volume) | 25.0 m³ | 883 ft³ |
| TEU | 1 | — |
* Typical value — varies by manufacturer
Types of tank containers
The workhorse is the general-purpose chemical tank (T11 class), but the family is wide. Baffled tanks add internal surge plates so partial loads can travel safely below the normal 80% fill floor. Food-grade tanks are dedicated stainless shells with sanitary fittings for juice, wine, oils and liquid food — never swapped with chemical service. Gas tanks (T50 class) are heavier pressure vessels for LPG, ammonia and refrigerant gases, and reefer tanks add heating or cooling to hold temperature-sensitive product in spec.
The T-codes themselves — T1 through T22 — come from the UN portable-tank rules and rank shells by test pressure and hazard capability: low numbers are light-duty tanks for benign liquids, T11 covers most non-hazardous and many hazardous chemicals, and higher codes like T14–T22 add thicker walls, higher test pressures and special fittings for aggressive or high-hazard cargoes. A tank may carry cargo requiring its own code or a lower one, never higher.
Fill rules
Dangerous-goods rules require tanks to travel between roughly 80% and 95% full: below 80% surge becomes dangerous, above 95% there is no room for thermal expansion. Baffled tanks are the exception for partial loads.
The rule shapes commercial practice: you size the shell to the parcel, not the other way round. A 25,000 L consignment would fill a 26,000 L tank to about 96% — just over the line — so it actually ships in a larger shell or splits across two tanks. Operators keep fleets of mixed capacities precisely to match parcels to the 80–95% window.
Frequently asked questions
How many litres does a tank container hold?
Standard shells range from about 21,000 to 26,000 litres; swap-body and specialty tanks go beyond 30,000 litres for light liquids.
How many gallons does an ISO tank hold?
About 5,550–6,870 US gallons, corresponding to the standard 21,000–26,000 litre shell range. The most common size, a 24,000 L tank, holds roughly 6,340 US gallons.
How much does a tank container weigh?
Tare weight is typically 3,600–4,400 kg depending on shell size and pressure rating. Maximum gross runs up to 36,000 kg on many modern tanks, allowing payloads over 32,000 kg where road limits permit.
How much does a tank container cost?
In 2025–26, used ISO tanks in serviceable condition typically sell for $12,000–20,000 — far above dry boxes, reflecting the stainless shell and pressure certification. Prices vary by market, location, T-code and remaining test validity.
Are tank containers the same size as normal containers?
The frame is exactly a 20 ft ISO footprint — 6.058 × 2.438 × 2.591 m — so it handles and stacks like any 20 ft box.
What do tank container T-codes mean?
T1–T22 classify portable tanks by test pressure and the hazard level of permitted cargoes under UN rules. T11 is the common general-chemical tank; T50 covers liquefied gases. A tank may carry cargo assigned to its own code or a lower one.