Conex Box Sizes: A Quick Guide
Conex boxes (also known as shipping containers, intermodal containers, ISO containers or sea boxes) are used worldwide for storage, transportation, and as the base for conversion projects like offices or homes.
The name ‘ConEx’ derives from their full name Container Express, which was the name under which they were first introduced to the US military during the 1950s. As such, Conex box is a term still used today, primarily in the USA in the military, construction, logistics and agricultural sectors.
Conex boxes are standardized by the International Organization for Standardization (ISO) to ensure uniform dimensions and specifications worldwide.
In this article we give an overview of standard and high cube Conex box sizes, as well as the Conex box corner casting dimensions.
Standard Conex Box Sizes & Dimensions
The most common Conex box sizes are 10-foot, 20-foot, 40-foot, and 45-foot containers. All standard Conex boxes are 8 feet wide and 8.5 feet tall, ensuring they can be stacked securely during transportation. Here is an overview with their typical dimensions:
All dimensions and weights are approximate as containers vary from manufacturer to manufacturer.
High Cube Conex Box Sizes
High cube Conex boxes are designed with an additional foot in height (9.5 feet tall). They are ideal for transporting very large cargo or for conversions, such as container homes or Conex offices, where the extra space provides more comfort. They come in 20-foot, 40-foot, and 45-foot sizes:
All dimensions and weights are approximate as containers vary from manufacturer to manufacturer. For more details on container sizes, including smaller and custom sizes, check out this article on shipping container dimensions.
Conex Box Corner Casting Dimensions
Corner castings allow all containers to be lifted, stacked, and secured during transport. The corner castings are made from Cortensteel and are located at each of the eight corners of the Conex box. Dimensions of the corner castings are the same for all ISO standard Conex containers, as well as for high cube containers.
The corner castings themselves measure: 7.01 inches x 6.38 inches x 4.65 inches (17.8 cm x 16.2 cm x 11.8 cm).
The front and side holes within the castings measure approximately 2.5 inches (63.5 mm) in both height and width, just slightly varying in shape depending whether they are at the top or the bottom of the container
Domino Clamp getting attached to a Conex corner casting to mount equipment for a conversion
Enhance Your Conex Box with Domino Clamps
Domino Clamps are a great solution to enhance the functionality of a Conex box and simplify modifications. These specially designed connectors attach to the corner castings of a Conex box, providing versatile mounting points for a variety of applications—without the need for welding or drilling.
Why Use Domino Clamps?
Domino Clamps offer a secure, efficient way to attach modifications to your Conex box, saving you time and effort - no welding and no drilling required. They're especially useful for conversion projects like Conex homes, offices, cafes, barns, or any other structures, where smart and reliable mounting is essential.
Applications for Domino Clamps:
- Installing solar panels
- Attaching frames or siding
- Securing stairs, awnings or roof structures
- Securing pipes, tubes, scaffolding and further structures
- Mounting utility poles for lights, cameras, antennas, Starlink etc.
Conex Box Accessories & Mounting Solutions
To explore how to incorporate these applications in your Conex conversions, check out our articles and guides on mounting solutions and Conex box attachments.
Watch our video explainer now to see how easy it is to enhance your Conex box projects!
