Container Types and Sizes for Miami Imports

Most Miami import cargo moves in one of four boxes: a 20ft standard, a 40ft standard, a 40ft high cube, or a 40ft reefer. The rest of the equipment catalogue exists for cargo that will not fit through a standard door or cannot sit on a standard floor. Choosing correctly matters less for the ocean rate than for what happens after the box lands, because a container that is legal to load overseas is not always legal to truck on a Florida highway.

The standard dry containers

20ft standard

Roughly 33 cubic meters of internal volume. This is the box for dense cargo: tile, stone, machinery, canned goods, liquids in drums. You will almost always run out of weight before you run out of space, which is exactly the point.

40ft standard

Roughly 67 cubic meters, or about twice the volume of a 20ft for considerably less than twice the ocean rate. This is the default for general merchandise of moderate density.

40ft high cube

Same footprint as a 40ft standard with about a foot of extra interior height, giving roughly 76 cubic meters. For light, bulky cargo — furniture, plastics, packaging, apparel — the high cube is usually the cheapest box per cubic meter you can buy. Confirm door height clearance at the receiving dock before you book one.

45ft high cube

Around 86 cubic meters. Less common and not accepted everywhere, but useful on lanes and at facilities that handle them. Chassis availability is the usual limiting factor, which our chassis guide discusses.

Specialized equipment

• Reefer (20ft and 40ft): temperature-controlled, essential for South Florida’s produce, seafood, flower and pharmaceutical trades. Reefers need power at every stage and a documented setpoint, and they must be pre-tripped before loading — see our post on reefer pre-trip inspections.
• Open top: a dry container with a removable tarpaulin roof, for cargo that must be craned in from above or that exceeds door height.
• Flat rack: a platform with collapsible or fixed ends, for cargo wider or taller than a box. Boats, transformers, and construction equipment ride on these. Handling is covered in our post on out-of-gauge drayage in Florida.
• ISO tank: for bulk liquids and some hazardous commodities.
• Ventilated: passive airflow, traditionally used for coffee and cocoa.

The Florida weight trap

This is the single most expensive container mistake Miami importers make. A 20ft container can legally hold far more cargo weight at sea than a tractor, chassis and container combination can legally carry on a US highway, where the standard gross vehicle weight limit is 80,000 pounds. Subtract tractor, chassis and container tare and you are typically left with somewhere around 43,000 to 45,000 pounds of payload, depending on equipment.

If your overseas supplier loads a 20ft to its ocean capacity, the box arrives legal on the vessel and illegal on the road. Your options at that point are an overweight permit, a transload into two trucks, or a partial devan at a warehouse — all of which cost more than simply telling the supplier a payload cap up front. Our posts on Florida truck weight limits and VGM and overweight container rules cover the details, and our drayage team flags likely overweights before the box is pulled.

Choosing the right box

Work it backwards. Calculate your cargo’s total cubic volume and total weight, then divide weight by volume to get density. Dense cargo above roughly 500 kilograms per cubic meter belongs in a 20ft. Light cargo belongs in a 40ft high cube. Anything that will not fit through a 7ft 8in door opening needs open top or flat rack. Anything with a temperature requirement needs a reefer with the setpoint on the booking, not in an email.

Frequently asked questions

What is the difference between a 40ft standard and a 40ft high cube?

The footprint is identical; the high cube is roughly one foot taller inside, giving about 76 cubic meters versus about 67. For light, bulky cargo the high cube is normally the lowest cost per cubic meter. Verify your receiving dock’s door and canopy clearance before booking one.

How much weight can I legally truck out of PortMiami in a 20ft container?

With an 80,000 pound gross vehicle weight limit and typical tractor, chassis and container tare, usable payload is generally around 43,000 to 45,000 pounds. Containers loaded above that overseas require an overweight permit, a transload, or a partial devanning before they can move legally on Florida roads.

When should I use a flat rack instead of an open top?

Use an open top when the cargo fits within the container’s width and length but exceeds door height or must be loaded from above. Use a flat rack when the cargo is wider than the container itself or needs to be secured to a platform, such as boats, transformers and large machinery.

Book the right equipment the first time

Go Freight is an asset-based 3PL at 3300 NW 110 St, Miami, FL 33167, handling drayage, transloading, devanning and warehousing for PortMiami and Port Everglades importers. Request a freight quote or call (786) 445-0150.