20ft vs. 40ft Shipping Containers: How to Choose for Storage
Choosing between a 20ft and 40ft shipping container starts with three questions: what will you store, how often will you need access, and what can your site accommodate? A larger container offers more room, but the best choice depends on the way you will use that space.
This guide compares standard dry containers for on-site storage. Explore NorCal’s 20ft shipping containers and 40ft shipping containers, then confirm the specifications and condition of the unit offered before ordering.
20ft vs. 40ft: usable space compared
The size in a container’s name is not its usable internal length. Walls, doors and the floor reduce the space available inside, and the door opening is smaller than the interior cross-section.
| Measurement | 20ft standard | 40ft standard |
|---|---|---|
| Example internal length | 5,900 mm (about 19.4 ft) | 12,032 mm (about 39.5 ft) |
| Example internal width | 2,352 mm (about 7.7 ft) | 2,352 mm (about 7.7 ft) |
| Example internal height | 2,395 mm (about 7.9 ft) | 2,395 mm (about 7.9 ft) |
| Example door opening, width × height | 2,340 × 2,292 mm | 2,340 × 2,292 mm |
| Example internal volume | 33.2 m³ | 67.7 m³ |
These are fleet examples from Hapag-Lloyd’s 20ft standard specifications and 40ft standard specifications, not guaranteed measurements for NorCal inventory. Dimensions vary by manufacturer. The example 40ft unit has just over twice the internal volume of the 20ft unit.
When a 20ft container makes sense
Start with a 20ft option if your storage list is relatively compact or you want to reserve more of the property for other uses. It is a useful size to evaluate for tools, seasonal equipment, household overflow or a smaller stockholding.
Before choosing, make a floor plan using the actual dimensions of your largest items. Include shelving depth and a walkway. A container that fits every box on paper may still be inconvenient if you have to unload the front half to reach something at the back.
When to consider a 40ft container
Consider a 40ft unit when you need longer uninterrupted storage space or expect your inventory to grow. Plan separate zones for frequently used items, bulk storage and equipment rather than treating all the extra volume as immediately usable capacity.
For example, a contractor could compare one larger storage area with two smaller units: the latter might separate tools from materials, while the former might suit longer items. Ask for both delivered quotes before deciding. Neither configuration is automatically the better value.
Check access before you choose the size
The delivery vehicle needs room beyond the container’s final footprint. Send NorCal photos of the entrance, approach and proposed placement area, along with details of gates, bends, slopes and overhead obstructions. Ask the team to confirm the access and unloading requirements for the proposed delivery method.
A smaller container does not guarantee successful delivery to a restricted site. Resolve access questions before arranging groundwork or placing an order.
Compare the full storage setup
- Delivered price: request a quote for the size, condition and delivery location you need. Avoid comparing a collection-only price with a delivered price.
- Condition: compare the actual units, including doors, seals, floor and visible repairs. If considering used shipping containers, ask what condition description applies.
- Access layout: allow for door operation, walkways and safe retrieval of stored items.
- Contents: ask whether your goods need humidity or temperature control beyond a basic dry container.
Questions to answer before requesting a quote
Write down your delivery ZIP code, intended contents, largest item dimensions, expected storage duration and preferred door orientation. Include whether the container is for storage only or another purpose, so the conversation starts with the right requirements.
Which size should you choose?
Choose the smallest option that comfortably supports your storage layout and expected growth, subject to site suitability. If both sizes work, compare their delivered costs and how easily you can organize and retrieve your belongings.
Request a NorCal Containers quote for your preferred size and ask the team to confirm availability, actual unit details and delivery access before you commit.