Container Loading Calculator
How many cartons or pallets fit a 20GP, 40GP, 40HC or 45HC, in which orientation, and whether cubic capacity or payload stops you. Built on carrier-published dimensions.
Cartons or Pallets, and What Binds First
Pick a container, enter one carton or pallet configuration, and read the fitted quantity, utilisation, gross weight and which limit you hit first.
Container
Carton
Pallet
Result
Runs entirely in your browser. Nothing you type is sent anywhere or stored.
| Vertical dimension | Floor footprint and pattern | Per layer | Layers | Cartons | Result |
|---|
A Rectangular Block Model, Not a Packing Solver
Read this before you use the number
It stacks one carton size in straight rows and columns, comparing six axis-aligned orientations and one mixed split. It is not a 3D bin-packing solver.
What the model leaves out
- Mixed carton sizes on one load, which has no clean formula.
- Irregular or protruding items that are not boxes.
- Dunnage, airbags, bracing and load-securing material.
- Working clearance the crew needs at the door end.
- Carton crush strength, which limits safe stack height.
- Weight distribution rules that keep the load balanced.
Under-counting is safe. Over-counting means a re-plan at the dock with the truck waiting.
Internal Dimensions and Payload Used Here
The figures the presets load, from one carrier's published dry container specifications.
| Container | Inside L × W × H | Door W × H | Capacity | Tare | Max payload | Max gross |
|---|---|---|---|---|---|---|
| 20' Standard (20GP) | 5,898 × 2,350 × 2,390 mm | 2,340 × 2,280 mm | 33.1 m³ | 2,150 kg | 28,330 kg | 30,480 kg |
| 40' Standard (40GP) | 12,032 × 2,350 × 2,390 mm | 2,340 × 2,280 mm | 67.6 m³ | 3,640 kg | 26,840 kg | 30,480 kg |
| 40' High Cube (40HC) | 12,032 × 2,350 × 2,695 mm | 2,340 × 2,585 mm | 76.2 m³ | 3,700 kg | 28,800 kg | 30,480 / 32,500 kg |
| 45' High Cube (45HC) | 13,556 × 2,352 × 2,697 mm | 2,340 × 2,585 mm | 86.0 m³ | 4,650 kg | 27,850 kg | 30,480 / 32,500 kg |
These are one carrier's figures, not a universal standard
Internal dimensions and payload vary by build, age and operator. Two containers of the same nominal size can differ by tens of millimetres and thousands of kilograms.
Confirm before you commit to a plan
- Ask your carrier for the specification of the equipment booked.
- Check the CSC plate on the door for tare, max gross and payload.
- Check the road weight limit between factory and port, often lower.
- Use the custom container option when your figures differ.
Source: Ocean Network Express dry container specifications, one-line.com/en/dry-containers, retrieved 14 August 2026.
How the Orientation Count Is Worked Out
Every figure here comes from the formulas below, simple enough to check by hand.
Single orientation
floor(CL / a) × floor(CW / b) × floor(CH / c) Assign the carton's dimensions a, b, c to the container's length, width and height. All six assignments are evaluated.
Mixed split, length bands
i × floor(CW / q) + floor((CL − i×p) / q) × floor(CW / p) Fill i bands of depth p along the length, then fill the leftover strip with cartons turned 90°. Every i is tested.
Mixed split, width bands
j × floor(CL / p) + floor((CW − j×q) / p) × floor(CL / q) The same idea rotated: bands run across the width, and the leftover strip is filled with cartons turned 90°.
| Step | What happens | Why it matters |
|---|---|---|
| Pick the vertical dimension | Each carton dimension is tried as the height, unless upright is enforced | Layers = floor(container height / vertical dimension) |
| Pack the floor | The other two dimensions are packed with pure and mixed patterns | The mixed split usually beats both pure orientations |
| Multiply | Cartons per layer × layers | Gives the cubic-capacity limit |
| Divide by weight | floor(max payload / carton gross weight) | Gives the payload limit |
| Take the lower | Fitted quantity is the smaller of the two | Names the binding constraint |
Why the mixed split earns its place
A 600 × 400 mm carton in a 40HC gives 100 per layer packed length-wise. Filling a single 400 mm band with turned cartons raises that to 110, a 10% gain.
The Constraint People Forget Is Weight
A container has two independent limits. Reporting only one is how loads get rejected at the gate.
Cube out
The container fills before the payload is reached. Typical of light bulky freight.
- Apparel, soft goods and bedding
- Homeware and plastic housewares
- Packaging, cups and empty containers
- Toys and flat-pack furniture
Lever: change the carton, not the container.
Weigh out
The payload is reached with space left. Typical of dense freight.
- Tiles, stone and ceramics
- Liquids in bottles or drums
- Batteries and power tools
- Fasteners, hardware and printed matter
Lever: split across containers, or lighten the packaging.
| Carton | Container | Gross weight | Limit by cube | Limit by payload | Fitted | Binds on |
|---|---|---|---|---|---|---|
| 600 × 400 × 300 | 40HC | 12 kg | 880 | 2,400 | 880 | Cube |
| 600 × 400 × 300 | 40HC | 35 kg | 880 | 822 | 822 | Payload |
| 600 × 400 × 300 | 20GP | 12 kg | 357 | 2,360 | 357 | Cube |
| 600 × 400 × 300 | 20GP | 80 kg | 357 | 354 | 354 | Payload |
| 400 × 300 × 250 | 20GP | 25 kg | 981 | 1,133 | 981 | Cube |
At 35 kg per carton the 40HC loses 58 cartons to the payload limit, dropping utilisation from 83.1% to 77.7%. The space is there; the weight allowance is not.
Why 85% Utilisation Is a Ceiling, Not a Target
The number returned is a geometric best case for a clean single-SKU stack. Real loads sit below it.
Where the missing percentage goes
- The strip at the door end, kept clear so the doors close.
- Void fill and airbags that stop the load shifting in transit.
- The gap above the top layer, unless the heights divide evenly.
- Pallet decks: 140 to 165 mm per tier, carrying no product.
- Mixed SKUs, which fragment the neat block pattern.
- Loading time, since the best pattern is rarely the fastest to build.
Palletising costs cube
The same carton gives 880 units loose in a 40HC but 660 on double-stacked 1200 × 1000 pallets: a quarter of capacity spent on handling speed and damage protection.
The Utilisation Number Decides the Mode
LCL is priced against the greater of your cubic metres or revenue tonnes. FCL is priced per container however full it is.
| Where your load sits | What it means | Usual move |
|---|---|---|
| Under a third of a 20GP | Most of the box ships empty | LCL, priced on actual cube |
| A third to most of a 20GP | The crossover zone | Price both door to door |
| Most of a 20GP | Paying for a box you nearly fill | FCL, and consolidate more into it |
| Over one container | The tail is the expensive part | Reshape the order, or send the tail LCL |
| Weighing out below full cube | Dense freight | FCL split; LCL revenue tonnes get costly |
Rates and consolidation schedules differ by lane and forwarder. Get both quotes before deciding.
A Carton Sized for a Shelf Can Cost You a Container
Carton dimensions are usually set by shelf depth, master pack count or a printer's tooling. The container never gets a vote, and the cost repeats on every shipment.
| Carton, all 0.072 m³ | Per layer | Layers | Per 40HC | Utilisation | Cube shipped |
|---|---|---|---|---|---|
| 600 × 480 × 250 mm | 95 | 10 | 950 | 89.8% | 68.4 m³ |
| 720 × 400 × 250 mm | 94 | 10 | 940 | 88.8% | 67.7 m³ |
| 800 × 300 × 300 mm | 115 | 8 | 920 | 86.9% | 66.2 m³ |
| 600 × 400 × 300 mm | 110 | 8 | 880 | 83.1% | 63.4 m³ |
| 500 × 480 × 300 mm | 100 | 8 | 800 | 75.6% | 57.6 m³ |
| 400 × 400 × 450 mm | 150 | 5 | 750 | 70.9% | 54.0 m³ |
Same volume, 27% difference in units shipped
Every carton above holds the same 0.072 m³ of product. The best shape ships 68.4 m³ per 40HC, the worst 54.0 m³. To move 1,000 m³ you need 15 containers instead of 19.
Check before tooling
Run any candidate carton through this calculator before the die is cut. Changing it later means new tooling, artwork and master pack counts.
Aim at a clean divisor
Dimensions that divide 2,350 mm and 12,032 mm with little left over waste less. A 10 mm change can move a whole row.
Recheck when you palletise
A carton that fits a container well may fit a pallet badly. Check both, since the pallet footprint binds in most warehouses.
The Door Is Smaller Than the Container
Internal width and height are what the cargo occupies once loaded. The door opening is what it must pass through, and it is always smaller.
| Container | Width, inside vs door | Height, inside vs door | Height lost |
|---|---|---|---|
| 20GP | 2,350 mm vs 2,340 mm | 2,390 mm vs 2,280 mm | 110 mm |
| 40GP | 2,350 mm vs 2,340 mm | 2,390 mm vs 2,280 mm | 110 mm |
| 40HC | 2,350 mm vs 2,340 mm | 2,695 mm vs 2,585 mm | 110 mm |
| 45HC | 2,352 mm vs 2,340 mm | 2,697 mm vs 2,585 mm | 112 mm |
Tall pallets
A pallet built to the full internal height cannot be driven through the door. Build to door height instead.
Forklift mast
The mast and forks need clearance above the load, taken from the door height rather than the internal height.
Long items
An item close to the internal length must be angled in, needing more width and height than the item itself.
Door figures come from the same carrier specification as the internal dimensions and vary the same way.
Shanghai to Long Beach, 40HC
A homeware brand ships a 600 × 400 × 300 mm carton at 12 kg gross from Shanghai to Long Beach in a 40' high cube, planned three ways.
| Mode | Fitted | Pattern | Utilisation | Gross weight | Binds on | Boxes for 5,000 |
|---|---|---|---|---|---|---|
| Loose, upright | 880 cartons | 110 per layer × 8 layers, mixed split | 83.1% | 10,560 kg | Cube | 6 |
| Loose, any orientation | 920 cartons | 230 per layer × 4 layers, laid on its side | 86.9% | 11,040 kg | Cube | 6 |
| Palletised, double stacked | 660 on 44 pallets | 22 positions × 2 tiers, 15 per pallet | 62.4% | 9,152 kg | Cube | 8 |
Reading the worked result
Payload is never the issue at 12 kg per carton, since 28,800 kg allows 2,400. Every option cubes out. The decision is whether faster handling justifies two extra containers.
How the palletised figure was built
- A 1200 × 1000 mm pallet takes 5 cartons per layer on the mixed split.
- A 1,300 mm limit leaves 1,138 mm above a 162 mm deck: 3 layers of 300 mm.
- So 15 cartons per pallet at a loaded height of 1,062 mm.
- Pallet gross is 15 × 12 kg plus a 28 kg deck, so 208 kg.
- Two tiers of 1,062 mm need 2,124 mm of the 2,695 mm available.
- The 40HC floor takes 22 positions, so 44 pallets and 660 cartons.
Overhang and pallet load ratings are covered in more detail by the pallet calculator.
Plan the Cube, the Pallet and the Carton
Container planning sits between carton design and freight booking.
Container Loading Questions
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