Container Load Calculator
Estimate how many cartons fit a 20′, 40′, 40′ high cube, and 45′ high cube — and see at a glance whether space or payload runs out first. Container specifications are published further down this page.
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), 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%)
- Cube 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), 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%)
- Cube 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), 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%)
- Cube 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), 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%)
- Cube used 73.7% of 86 m³
- 1 container(s) for 500 cartons
Orthogonal floor-load estimate: one carton size, best of the six axis-aligned orientations, stacked in a regular block. No pallets, dunnage, bracing, or mixed orientations are modelled. Estimates for planning; the carrier's tariff and the equipment supplied govern.
Container specifications
Internal dimensions, door openings, tare, payload, and cubic capacity for the four dry container types this 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, and this calculator estimates how many fit into 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 built on published internal dimensions; the carrier’s tariff and the equipment actually supplied govern the real load.
How this estimate is calculated
The calculator tries all six axis-aligned orientations of your carton — every way a rectangular box can sit with its faces parallel to the container walls — and keeps the one that yields the most pieces. For each orientation it divides the container’s internal length, width, and height by the carton’s corresponding dimension, rounds each down to a whole number, and multiplies the three counts together.
That is a floor-loaded, single-orientation block: every carton the same way up, stacked in a regular grid, no mixing of orientations, no rotated end rows, no pallets, no dunnage or airbags, and no allowance for a bulkhead or lashing. It is deliberately not a 3D bin-packing solver. Real stuffing plans usually land a few percent below the geometric number once bracing and irregular last rows are accounted for, and occasionally above it when a loader mixes orientations in the door end.
Weight is applied as a second, independent cap: the container’s payload divided by the weight of one carton. Whichever cap is lower is what a container can actually take, and the tool labels which one binds.
When weight binds before volume
A 20′ container holds roughly 33 cubic metres but carries close to 28 tonnes, so anything denser than about 850 kg per cubic metre fills its payload before it fills its cube. Stone, tiles, machinery, fasteners, tinned food, and liquids routinely load 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 constraint that binds to be the one you are paying for.
The reverse case — volume binding first — is the norm for furniture, apparel, plastics, packaging, and most consumer goods. There, stepping from a 40′ GP to a 40′ HC often buys an extra tier of cartons for a modest difference in cost, and a 45′ HC adds roughly another 13% of cube on top.
Payload, tare, and the limits that really apply
Payload is the container’s maximum gross weight less its tare — the empty weight of the box itself. Both numbers are stamped on the CSC safety-approval plate on the door, and they vary between individual units, so treat the figures in the specification table as typical published values rather than the limit for your specific container.
The container’s own payload is rarely the binding constraint in practice. 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 means a standard chassis and tractor combination can often only legally move a fraction of a container’s rated payload without an overweight permit or a specialised chassis. Ports, rail ramps, and some inland corridors add their own caps. Plan the load around the tightest leg of the route, not around the plate.
Verified Gross Mass also applies: under SOLAS the shipper must declare the VGM — cargo plus dunnage plus tare — before the box can be loaded to a vessel. The calculator’s loaded weight plus the tare in the table gives you a working VGM estimate to check against the limit.
Getting more into the box
Small changes to carton geometry compound. 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, and shaving a centimetre off carton height can add a whole tier. Run a couple of variants through the calculator before you finalise packaging — it is the cheapest optimisation available to an importer.
If the volume never reaches a full container, LCL consolidation prices per revenue ton instead, and the crossover is usually somewhere around 13–15 cubic metres. Work out your CBM and revenue tons with the chargeable weight calculator, then compare.
Booking a full container? See how we move FCL ocean freight. Not enough volume to fill one? LCL consolidation prices per revenue ton — work yours out with the chargeable weight and CBM calculator.
It depends entirely on 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 metres — and a payload near 28 tonnes. Enter your carton dimensions above and the calculator estimates the count for a 20′, 40′, 40′ HC, and 45′ HC, and flags whether space or weight runs out first.
Approximately 12.03 m long, 2.35 m wide, and 2.70 m high internally, with a door opening around 2.34 m wide by 2.58 m high and a cubic capacity near 76 m³. That is roughly 30 cm more internal height than a standard 40′, which is often one additional tier of cartons. Full figures for all four sizes are in the container specifications table on this page.
The container’s payload is its maximum gross weight less its tare, shown on the CSC plate — typically around 28 tonnes for a 20′ and 26–27 tonnes for a 40′. Road weight limits at origin and destination usually cap the practical load well below that, so confirm the legal limit for the trucking leg before you plan to load to the plate.
Compare which limit binds. Dense cargo — stone, tiles, machinery, liquids — usually hits the weight cap, and two 20′ containers carry more total weight than one 40′. Light, bulky cargo hits the volume cap, so a 40′ or 40′ high cube moves far more per container. The calculator shows the binding constraint for each size side by side.
It is a geometric estimate: one carton size, one orientation per plan, floor-loaded in a regular block, with the best of the six axis-aligned orientations chosen. It excludes pallets, dunnage, bracing, mixed orientations, and irregular door-end rows, so a real stuff plan typically comes in a few percent lower. Use it for planning and equipment selection, not as a loading instruction.
Not directly. If your cargo ships palletised, enter the dimensions and weight of the loaded pallet as the "carton" — footprint including any overhang, total height including the pallet deck, and gross weight including the pallet itself. That gives a realistic pallet-position count for each container size.
Because the cargo has to get through the doors. A door opening is a little narrower and noticeably lower than the internal cross-section, particularly on high cubes, so oversized or non-stackable items can clear the interior yet fail at the doorway. The calculator flags this when the two smallest dimensions of your carton exceed the door opening.
Customs entries are based on the goods, their classification, and their value rather than container weight, though the packing list and bill of lading carry gross weights that should agree with 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 alongside your booking.
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