# Tank Container Dimensions

Source: https://contsize.com/tank-container/ · CC BY 4.0 · checked 2026-10-19

A tank container (ISO tank) most often holds 25,000 litres (about 6,600 US gallons) of liquid, per 5 of 6 sheets, in a stainless-steel vessel inside a standard 20 ft frame of 6.058 × 2.438 × 2.591 m (19′10½″ × 8′ × 8′6″), per ISO 668. Shells on the sheets range 20,000–26,000 litres; tare is 3,040–3,920 kg, about 3,640 kg, with [max gross](https://contsize.com/glossary/max-gross/) up to 36,000 kg, so dense liquids hit the weight limit before the volume limit. The UN dangerous-goods rules keep a shell out of the band between 20% and 80% full unless it is divided into sections of 7,500 litres or less, and cap the fill at 97% less the room the liquid needs to expand.

*20 ft tank container: dimensions and weight*

|  | Metric | Imperial |
| --- | --- | --- |
| External dimensions | **6.058 × 2.438 × 2.591 m** | 19′10½″ × 8′ × 8′6″ |
| Tank capacity | **25.0 m³** | 883 ft³ |
| Tare weight | **3,640 kg** | 8,025 lb |
| Max payload | **32,360 kg** | 71,342 lb |

[Types of shipping containers](https://contsize.com/types-of-shipping-containers/)

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.

![Drawing of a tank container: a steel cylinder held inside a 20 ft frame.](https://contsize.com/figures/tank-container-isometric-drawing-en.png)

**The numbers in this chart**

*Tank container: what it looks like*

| Figure | Value |
| --- | --- |
| Outside, L × W × H | 6.058 × 2.438 × 2.591 m |
| Capacity | 25.0 m³ |
| Payload | 32,360 kg |

Checked 19 October 2026: outside sizes set by ISO 668, read in IS 6566:2001, GOST R 51876-2008 and GOST R 53350-2009; every other figure against 7 published sheets of 5 lines and lessors. A sheet agrees within ±5 mm, or ±2 % for a mass and ±1 % for a volume; a maximum gross is a rating and must be the same. [Every figure and its sources](https://contsize.com/container-data-sources/#c-20ft-tank)

*Tank container: what it looks like*

Typical shells hold 20,000 to 26,000 litres, and 25,000 litres is the size most sheets print. 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 arithmetic is plain: one 25,000 L tank holds what 125 drums of 200 L each hold, loads and discharges through one hose connection instead of 125 bungs, and returns clean from a certified depot for the next product.

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. The UN rules have the shell inspected and pressure-tested every 5 years, with an intermediate inspection halfway, every 2.5 years.

![Bar chart of maximum payload for double door, reefer, open top, flat rack and tank containers beside a dry 40 ft high cube.](https://contsize.com/figures/special-container-types-payload-en.png)

**The numbers in this chart**

*Payload of the special container types against a dry high cube*

| Container | kg | lb |
| --- | --- | --- |
| [40 ft high cube container](https://contsize.com/40-ft-high-cube-container/) | 28,670 | 63,207 |
| 40 ft HC double door container | 26,730 | 58,930 |
| [40 ft high cube reefer](https://contsize.com/reefer-container/) | 29,380 | 64,772 |
| [40 ft open top](https://contsize.com/open-top-container/) | 26,630 | 58,709 |
| [40 ft flat rack](https://contsize.com/flat-rack-container/) | 40,000 | 88,185 |
| [20 ft flat rack](https://contsize.com/flat-rack-container/) | 31,060 | 68,476 |
| 20 ft tank container | 32,360 | 71,342 |

Checked 19 October 2026: the figures in this chart against 44 of 88 published sheets from 20 lines, lessors and makers: those that print these figures. A sheet agrees within ±5 mm, or ±2 % for a mass and ±1 % for a volume; a maximum gross is a rating and must be the same. [Every figure and its sources](https://contsize.com/container-data-sources/)

*Payload of the special container types against a dry high cube*

## 20 ft tank container: dimensions and weight

*20 ft tank container22T1*

|  | Metric | Imperial |
| --- | --- | --- |
| External dimensions |  |  |
| Length | 6.058 m | 19′10½″ |
| Width | 2.438 m | 8′ |
| Height | 2.591 m | 8′6″ |
| Specification |  |  |
| Tare weight | 3,640 kg | 8,025 lb |
| Max gross weight | 36,000 kg | 79,366 lb |
| Max payload | 32,360 kg | 71,342 lb |
| Tank capacity | 25.0 m³ | 883 ft³ |
| TEU | 1 |  |

Checked 19 October 2026: outside sizes set by ISO 668, read in IS 6566:2001, GOST R 51876-2008 and GOST R 53350-2009; every other figure against 7 published sheets of 5 lines and lessors. A sheet agrees within ±5 mm, or ±2 % for a mass and ±1 % for a volume; a maximum gross is a rating and must be the same. [Every figure and its sources](https://contsize.com/container-data-sources/#c-20ft-tank)

Data: [ISO 668 (1995 text, read in IS 6566:2001)](https://contsize.com/citations/#iso-668) · [CMA CGM Equipment Guide](https://contsize.com/citations/#cma-specs) · Crowley, Seaco, SeaCube, VTG

## 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 a partial load may travel between 20% and 80% full, which the rules allow when each section holds 7,500 litres or less. 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 — are the UN portable-tank instructions for liquids and solids, and they rank shells by minimum test pressure, shell thickness and openings: T1 is tested at 1.5 bar, T11 to T14 at 6 bar and T15 to T22 at 10 bar, and T20 to T22 call for shells of 8 to 10 mm of reference steel. T11 is the standard tank on the lessors’ sheets. A cargo assigned one code may also travel in a stricter tank the rules list for it — for T11, any of T12 to T22 — never in a lighter one.

## Fill rules

The UN Model Regulations (4.2.1.9) set the limits. A shell may not travel more than 20% but less than 80% full, where surge becomes dangerous, unless partitions or surge plates divide it into sections of 7,500 litres or less. The top limit is 97% less the room the liquid needs to expand at the warmest it may get in transit, and 95% less that room for toxic (Division 6.1) and corrosive (Class 8) liquids of packing groups I and II. A heated cargo may fill a shell to 95% at most at any time, whatever its expansion. The International Tank Container Organisation recommends 95% for every cargo, as many operators require.

The rule shapes commercial practice: you size the shell to the parcel, not the other way round. A 25,000 L parcel would fill a 26,000 L tank to about 96%, over the 95% many operators allow, so the shipper trims the parcel or books a shell it fills within the window. Operators keep fleets of mixed capacities to land each parcel between 80% and the top limit.

## Frequently asked questions

**How many litres does a tank container hold?**

A tank container most often holds 25,000 litres (25.0 m³, about 6,600 US gallons), per 5 of 6 sheets; the sheets we read print shells from 20,000 to 26,000 litres. A swap-body tank on a longer frame holds more: 35,000 litres, from one sheet (Seaco).

**How many gallons does an ISO tank hold?**

The most common ISO tank, 25,000 litres, holds about 6,600 US gallons, per 5 of 6 sheets. The shells on the sheets we read, 20,000–26,000 litres, are about 5,280–6,870 US gallons.

**How much does a tank container weigh?**

An empty 20 ft tank container weighs about 3,640 kg (8,025 lb), depending on shell size and pressure rating — sheets print 3,040–3,920 kg. Maximum gross runs up to 36,000 kg on many modern tanks, per all 6 sheets, allowing a [payload](https://contsize.com/glossary/payload/) of about 32,360 kg where road limits permit.

**How much does a tank container cost?**

We quote no price for an ISO tank: no two dealers we read publish one, and a tank’s value turns on its T-code, its remaining test validity and its last cargo rather than on its age. Ask a lessor or a tank dealer for a quote on a named unit.

**Are tank containers the same size as normal containers?**

Yes: the frame is exactly a 20 ft ISO footprint, 6.058 × 2.438 × 2.591 m (19′10½″ × 8′ × 8′6″), per ISO 668, so it handles and stacks like any 20 ft box.

**What do tank container T-codes mean?**

T1–T22 are the UN portable-tank instructions for liquids and solids, ranked by minimum test pressure (1.5 bar for T1 up to 10 bar for T15 to T22), shell thickness and openings. T11, tested at 6 bar, is the standard tank on the lessors’ sheets; T50 covers liquefied gases under pressure. A cargo assigned one code may also travel in a stricter tank the rules list for it, never in a lighter one.

**Why is it called an ISO tank?**

Because the frame is built to ISO 668 dimensions and carries ISO 6346 markings like any other container: 6.058 × 2.438 × 2.591 m (19′10½″ × 8′ × 8′6″) with standard [corner castings](https://contsize.com/glossary/corner-casting/). That is the whole point of the design — an ISO tank drops into any 20 ft slot on any ship, chassis or railcar worldwide.

## Related pages

- [20 ft container6.058 × 2.438 × 2.591 m · 33.2 m³](https://contsize.com/20-ft-container/)
- [Shipping container weightTare · Payload · Max gross · VGM](https://contsize.com/shipping-container-weight/)
- [Container size chart (all 17)17 containers · Metric and imperial · Prints on one sheet](https://contsize.com/shipping-container-dimensions-chart/)
- [ISO container standardsISO 668 · ISO 6346 · CSC](https://contsize.com/iso-container-standards/)
- [Unit convertermm · cm · m · in · ft](https://contsize.com/unit-converter/)
- [Bulk containerISO 22B0 · bulk](https://contsize.com/bulk-container/)