Choose a size · UK guide
Shipping container dimensions: choose the space you need
Use external dimensions to plan the footprint, internal dimensions to arrange your goods, and the door opening to check entry. A container described as 20ft does not provide 20ft of usable internal length. Start with your largest item and the delivery site, then compare formats.
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Three measurements, three different decisions
The comparison below uses identified fleet examples. Internal dimensions and openings vary with the manufacturer, door arrangement and any lining. Ask the seller for the specification of the unit being quoted, particularly when a clearance is tight.
The names 20ft and 40ft are commercial size classes. The 20ft example has an external length of 6,058 mm, rather than the 6,096 mm obtained by converting exactly 20 feet. A standard height is 8ft 6in; a high cube is 9ft 6in. The additional height does not make the container wider.
| Measurement | Use it for | What to add |
|---|---|---|
| External length × width × height | Space occupied by the box | Door swing, access, maintenance and any supports |
| Internal clear dimensions | Racking, stored goods or a fit-out | Aisles, packaging and finished lining thickness |
| Door clear width × height | Whether an item can enter upright | Pallet/skid height and handling clearance |
Compare sizes and check a door opening
All inputs are in millimetres. Enter 0 only when a dimension is genuinely zero; a blank remains unknown. Decimals may use a dot or comma. Dimensions must be between 0 and 20,000 mm; item width and height must be greater than zero.
Hapag-Lloyd 22 G1 fleet example. Confirm the specification of the actual unit.
| Size | Outside | Inside | Door |
|---|---|---|---|
| 20ft standard | 6.058 × 2.438 × 2.591 m | 5.900 × 2.352 × 2.395 m | 2.340 × 2.292 m |
| 40ft standard | 12.192 × 2.438 × 2.591 m | 12.032 × 2.352 × 2.395 m | 2.340 × 2.292 m |
| 40ft high cube | 12.192 × 2.438 × 2.896 m | 12.032 × 2.350 × 2.700 m | 2.340 × 2.597 m |
Complete all four fields with valid values to check the cross-section.
Upright rectangular cross-section only. No rotation, ramp, turning path, forklift, floor loading or lifting assessment. Zero spare clearance means an exact mathematical fit, not practical loading approval.
Your entries remain in this page until you choose to add them to the editable quote form. That click does not send a request.
Choose around the job, not the cubic capacity
A long container can hold more stock but may require a different delivery vehicle and a larger manoeuvring area. Check the position and access route before ordering. Two smaller units introduce two delivery positions and separate doors, so compare the complete arrangement.
For regular access, draw your shelves and walking route on the floor plan. For occasional bulk storage, measure the largest packaged item and identify which goods can actually stack. Dividing the total cubic capacity by the volume of one box ignores gaps, handling and weight.
- Long materials: compare their full packaged length with the internal length.
- Tall equipment: check door height as well as the ceiling; a pallet adds to the entry height.
- Heavy items: obtain their mass and support footprint. Payload alone does not validate the floor loading.
- A fitted workshop: include partitions, finishes, service runs and clear access to doors.
Check mass separately from dimensions
A container with sufficient floor space may still be unsuitable for the load or handling operation. Obtain the actual tare, maximum gross mass and details of the heaviest items. Added linings, racking, pallets and securing material affect the total.
Use the weight guide to distinguish those figures and calculate a loaded estimate. For a pallet layout, use the packed footprint rather than the nominal wooden base. For mixed furniture or equipment, a measured inventory exposes the longest items and unknown masses before you ask for a unit.
Calculate tare plus contents →Draw a pallet floor plan →Build a storage inventory →
Measure in the order that can rule an option out
First compare the largest packaged item with the door, then the space inside, and finally the handling route. A long item that would fit once inside may still be impossible to turn through the opening. Keep its required orientation and support equipment in the brief.
Next mark the installed footprint and the open-door area on the site drawing. The dimensions table describes the box, not the operating space beside it or the space a delivery vehicle needs. Ask the supplier to confirm the door swing, approach and unloading position on the same drawing.
| Check | Measure or request | Common omission |
|---|---|---|
| Door entry | Clear width and height of the actual opening | Pallet, packaging or lifting attachment adds height |
| Final internal position | Finished dimensions after all fitted layers | Racking, linings and protrusions reduce clear space |
| Retrieval and operation | Space to turn, work and reach the goods | A fully occupied floor leaves no useful access |
| Installed site | External footprint, door swing and delivery access | The lorry needs more space than the container |
10ft, side opening and refrigerated units
A 10ft storage container may be purpose-built or cut down from a longer unit. Do not halve a 20ft specification to estimate its dimensions. Request its actual clear opening, floor dimensions and empty mass.
A side-opening container can make long items easier to load, but its opening, doors and site clearance need their own drawing. Refrigerated containers lose usable space to insulation, machinery and air circulation. Their marked loading limit can be below the physical ceiling.
10ft container options →Side-opening containers →Prepare a refrigerated-container brief →
Measurements to include in a quote request
Give the supplier your intended use, largest item dimensions including packaging, the required aisle or working space, and your postcode. Include photographs of the access route and proposed position separately when the supplier asks for them. The footprint drawing is not a lifting plan.
- Selected size and whether the unit is standard height or high cube.
- Minimum internal dimensions and door opening you need.
- Purchase or hire, condition, and any lining, racking or additional doors.
- Delivery position, overhead obstructions, ground condition and who will unload.
Questions before you choose
Are all 20ft containers the same inside?
No. The size class describes the general format. Manufacturer, flooring, door construction and modifications affect the usable space. Confirm the actual unit's dimensions.
Does a high cube have a larger floor?
In the examples shown, standard and high cube 40ft units have almost the same floor dimensions. The main difference is height. A lined high cube can still have less space than an unlined specification suggests.
Does passing the door check guarantee that I can load the item?
No. It checks an upright rectangular cross-section only. Approach angle, ramps, floor strength, lifting equipment, load distribution and safe working space remain to be checked.