Container Load Calculator
See how many of your cartons fit in a 20′, 40′, 40′ high cube or 45′ high cube container, how many containers your order needs, and whether space or payload runs out first. Internal dimensions, door openings and payloads are in the container specifications table.
Each carton is 0.096 CBM · total shipment 48 CBM and 9,000 kg gross.
20′ General Purpose
20GP9 along the length × 5 across × 5 tier(s), with each carton placed 60 × 40 × 40 cm.
Space limit binds first: the container fills up before the payload does.
- Space allows 225 · payload allows 1,568
- Loaded weight 4,050 kg of 28,230 kg payload (14.3%)
- Space used 65.1% of 33.2 m³
- 3 container(s) for 500 cartons
40′ General Purpose
40GP20 along the length × 5 across × 5 tier(s), with each carton placed 60 × 40 × 40 cm.
Space limit binds first: the container fills up before the payload does.
- Space allows 500 · payload allows 1,485
- Loaded weight 9,000 kg of 26,730 kg payload (33.7%)
- Space used 70.9% of 67.7 m³
- 1 container(s) for 500 cartons
40′ High Cube
40HC20 along the length × 5 across × 6 tier(s), with each carton placed 60 × 40 × 40 cm.
Space limit binds first: the container fills up before the payload does.
- Space allows 600 · payload allows 1,474
- Loaded weight 10,800 kg of 26,540 kg payload (40.7%)
- Space used 75.5% of 76.3 m³
- 1 container(s) for 500 cartons
45′ High Cube
45HC22 along the length × 5 across × 6 tier(s), with each carton placed 60 × 40 × 40 cm.
Space limit binds first: the container fills up before the payload does.
- Space allows 660 · payload allows 1,538
- Loaded weight 11,880 kg of 27,700 kg payload (42.9%)
- Space used 73.7% of 86 m³
- 1 container(s) for 500 cartons
Planning estimate: one carton size, stacked the same way up in a regular block, using the best of six orientations. Pallets, dunnage, bracing and mixed orientations are not modeled. The carrier's tariff and the equipment supplied decide the real load.
Container specifications
Typical internal dimensions, door openings, tare, payload and capacity for the four dry container types the calculator covers.
| Container | ISO type | Internal L × W × H (m) | Door opening W × H (m) | Tare (kg) | Max gross (kg) | Payload (kg) | Capacity (m³) |
|---|---|---|---|---|---|---|---|
| 20′ General Purpose | 22G1 | 5.898 × 2.352 × 2.393 | 2.34 × 2.28 | 2,250 | 30,480 | 28,230 | 33.2 |
| 40′ General Purpose | 42G1 | 12.032 × 2.352 × 2.393 | 2.34 × 2.28 | 3,750 | 30,480 | 26,730 | 67.7 |
| 40′ High Cube | 45G1 | 12.032 × 2.352 × 2.698 | 2.34 × 2.585 | 3,940 | 30,480 | 26,540 | 76.3 |
| 45′ High Cube | L5G1 | 13.556 × 2.352 × 2.698 | 2.34 × 2.585 | 4,800 | 32,500 | 27,700 | 86.0 |
- 20GP — The workhorse box for dense cargo. It usually hits its weight limit long before it fills up.
- 40GP — Twice the floor of a 20′ but a lower payload, because the box itself weighs more.
- 40HC — About 30 cm of extra internal height — often one more carton tier for light, bulky cargo.
- 45HC — Roughly 13% more cube than a 40′ HC. Availability is thinner and some inland routings restrict it.
Source. ISO 668 series-1 freight container dimensions, cross-checked against published carrier equipment guides (Maersk, MSC, Hapag-Lloyd container specification pages).
Internal dimensions, tare, and payload vary by build year, manufacturer, and carrier. The binding figures for any individual unit are stamped on its CSC safety-approval plate. Payload here is the maximum gross weight less the tare shown, and road weight limits at either end frequently cap the usable payload well below it. Last reviewed 2026-09-03.
Enter one carton size, the quantity and the weight per carton. The calculator estimates how many cartons fit in a 20′, 40′, 40′ high cube and 45′ high cube, and tells you whether space or payload runs out first. It is a planning estimate based on published internal dimensions; the carrier’s tariff and the equipment actually supplied decide the real load.
Heavy cargo fills the payload, light cargo fills the space
A 20′ container holds roughly 33 cubic meters but carries close to 28 metric tons. Anything denser than about 850 kg per cubic meter hits the weight limit before it fills the box. Stone, tiles, machinery, fasteners, canned food and liquids routinely fill a 20′ only halfway up the walls.
That is why heavy cargo ships in 20′ boxes and light, bulky cargo ships in 40′ high cubes. You pay per container either way, so you want the limit you hit to be the one you are paying for.
For furniture, apparel, plastics, packaging and most consumer goods, space runs out first. Moving from a 40′ standard to a 40′ high cube often adds another tier of cartons for a modest difference in cost, and a 45′ high cube adds roughly 13% more cube again.
Getting more into the box
Small changes to carton size add up. A carton whose footprint divides evenly into the 2.35 m internal width wastes far less floor than one that leaves a 30 cm strip down the side. Taking a centimeter off carton height can add a whole tier. Try a couple of carton sizes in the calculator before you finalize packaging; it is the cheapest saving available to an importer.
If you won’t fill a full container, LCL consolidation prices per revenue ton instead, and the crossover is usually around 13–15 cubic meters. Work out your CBM and revenue tons with the chargeable weight calculator, then compare.
Payload, tare and the weight limits that really apply
Payload is the container’s maximum gross weight minus its tare, the weight of the empty box. Both numbers are stamped on the CSC safety-approval plate on the door and vary from one container to the next. Treat the figures in the specifications table as typical published values, not the limit for your specific container.
In practice, the container’s own payload is rarely what stops you. Road weight limits at origin and destination usually cap the load first. In the United States, the federal gross vehicle weight limit on the Interstate system often means a standard chassis and tractor can legally move only a fraction of a container’s rated payload without an overweight permit or a specialized chassis. Ports, rail ramps and some inland corridors set their own caps. Plan the load around the tightest leg of the route, not around the plate.
Verified Gross Mass (VGM) also applies. Under SOLAS, the shipper must declare the VGM (cargo plus dunnage plus tare) before the container can be loaded onto a vessel. Add the calculator’s loaded weight to the tare in the table for a working VGM estimate to check against the limit.
How the estimate is calculated
The calculator tries all six ways a rectangular carton can sit square to the container walls and keeps the one that fits the most. For each, it divides the container’s internal length, width and height by the matching carton dimension, rounds each result down to a whole number, and multiplies the three together.
That gives a floor-loaded block with every carton the same way up. It does not mix orientations, rotate end rows, or allow for pallets, dunnage, airbags, bulkheads or lashing. It is deliberately not a 3D bin-packing solver. Real stuffing plans usually come in a few percent below the geometric number once bracing and uneven last rows are counted, and occasionally above it when a loader mixes orientations at the door end.
Weight is a second, separate cap: the container’s payload divided by the weight of one carton. The lower of the two caps is what a container can actually take, and each result card shows which one applies.
Filling a container? See how we handle FCL ocean freight. Not enough to fill one? LCL consolidation prices per revenue ton; work out yours with the chargeable weight and CBM calculator.
Terms on this page:High Cube ContainerCubic Meter (CBM)Verified Gross Mass (VGM)DunnageLashing
It depends on your carton size and weight. A 20′ general purpose container has roughly 5.90 m × 2.35 m × 2.39 m of internal space (about 33 cubic meters) and a payload near 28 metric tons. Enter your carton dimensions above to get an estimated count for a 20′, 40′, 40′ HC and 45′ HC, and to see whether space or weight runs out first.
Approximately 12.03 m long, 2.35 m wide and 2.70 m high inside, with a door opening around 2.34 m wide by 2.58 m high and a capacity near 76 m³. That is roughly 30 cm more internal height than a standard 40′, which is often one more tier of cartons. The specifications table on this page has full figures for all four sizes.
On paper, the payload shown on the CSC plate: the maximum gross weight minus the tare, typically around 28 metric tons for a 20′ and 26–27 metric tons for a 40′. In practice, road weight limits at origin and destination usually cap the load well below that, so confirm the legal limit for the trucking leg before you plan to load to the plate.
Use a 20′ for dense cargo and a 40′ or 40′ high cube for light, bulky cargo. Stone, tiles, machinery and liquids usually hit the weight limit, and two 20′ containers carry more total weight than one 40′. Light, bulky cargo hits the space limit, so a 40′ or 40′ high cube moves far more per container. The calculator shows which limit you hit in each size, side by side.
Close enough for planning and choosing equipment, but not a loading instruction. It assumes one carton size, stacked the same way up in a regular block, using the best of the six possible orientations. It leaves out pallets, dunnage, bracing, mixed orientations and uneven door-end rows, so a real stuffing plan typically comes in a few percent lower.
Not directly, but you can enter a loaded pallet as the "carton". Use the footprint including any overhang, the total height including the pallet deck, and the gross weight including the pallet itself. That gives a realistic count of pallet positions for each container size.
Because the cargo has to get through the doors first. The door opening is a little narrower and noticeably lower than the inside of the container, especially on high cubes, so an oversized or non-stackable item can fit the interior but not the doorway. The calculator warns you when your carton’s two smallest dimensions are larger than the door opening.
Not as a separate figure. Customs entries are based on the goods, their classification and their value, not the container weight, though the gross weights on your packing list and bill of lading should match what was loaded. Separately, SOLAS requires a Verified Gross Mass declaration to the carrier before loading. We coordinate entries through our licensed customs broker network and can walk you through the VGM process with your booking.
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