Dividing the container volume by the box volume overstates what fits, because boxes cannot be cut to fill the last few centimetres along each wall. A 20 ft container holds about 33 m³, but whether you can load 1,000 or 1,200 cartons depends on how their sides divide into 5.90 × 2.35 × 2.39 m.
This calculator stands the box on each of its three faces in turn, finds the best floor pattern – a plain grid, the grid turned 90°, or a mix of rows in both directions – and stacks as many layers as the height allows. If there is a gap above the top layer, it also tries to fill it with boxes laid on their side. Tick “keep upright” for goods marked “this way up”; then only the rotation on the floor is allowed.
The result lists the number of boxes, how many per layer and how many layers, the volume utilisation and a step-by-step plan. Container sizes are typical inside dimensions; individual containers vary by a few centimetres, doors are slightly smaller than the inside, and the payload limit (about 28 t for a 20 ft and 26–28 t for a 40 ft) can stop you before the space does.
How to use the Container Loading Calculator
- Container type
- Container’s inside length
- Container’s inside width
- Container’s inside height
- Package length (side A)
- Package width (side B)
- Package height (side C)
- Orientation
- Weight per package (optional)
Everything is calculated in your browser, so results appear instantly and nothing you type is sent to a server.
How it works
For each choice of vertical side the floor is packed with two guillotine patterns (k rows in one direction, the rest turned 90°) and the best count is kept; layers = ⌊height ÷ vertical side⌋. The remaining headroom is filled with other orientations where possible, and the best total wins.
Worked example
5 × 5 × 5 inch cubes (12.7 cm) in a 20 ft standard container: 590 ÷ 12.7 = 46, 235 ÷ 12.7 = 18 and 239 ÷ 12.7 = 18 whole cubes, so 46 × 18 × 18 = 14,904 packages, using 92% of the space. The volume-only estimate, 33.14 m³ ÷ 0.002048 m³ ≈ 16,177, cannot be reached because of the gaps along the walls.
Container sizes used
| Type | Inside L × W × H (m) |
|---|---|
| 10 ft standard | 2.83 × 2.35 × 2.39 |
| 20 ft standard | 5.90 × 2.35 × 2.39 |
| 40 ft standard | 12.03 × 2.35 × 2.39 |
| 20 ft high cube | 5.90 × 2.35 × 2.69 |
| 40 ft high cube | 12.03 × 2.35 × 2.69 |
| 45 ft high cube | 13.56 × 2.35 × 2.69 |
| 20 ft pallet-wide | 5.89 × 2.44 × 2.39 |
| 40 ft pallet-wide | 12.02 × 2.44 × 2.39 |
Tips
- Measure the longest points of the package, including bulges.
- Check your carrier’s current divisor and rounding rules.
- Every field has a unit menu – cm, inches, kg and lb all work.
- Everything is calculated in your browser.
Common mistakes to avoid
- Using the wrong dimensional divisor for the carrier or service.
- Forgetting pallet height and overhang limits.
- Rounding dimensions down instead of up.
Formula
Boxes = boxes per layer × layers (+ boxes laid sideways in the gap above) · per layer = best mix of ⌊L ÷ a⌋ × ⌊W ÷ b⌋ and the 90° turned pattern · utilisation = boxes × box volume ÷ container volume
Worked example
Inputs — Container type: 20 ft standard; Package length (side A): 50 cm; Package width (side B): 40 cm; Package height (side C): 30 cm; Orientation: Any – boxes may be turned on their side; Weight per package (optional): 0 kg.
Results — Packages that fit = 500; Packages per layer = 109; Full layers = 4; Space utilisation = 90.53 %; Volume of one package = 0.06; Container volume = 33.1374.
Key terms
- Utilisation
- Share of the container volume filled by cargo.
- High cube
- Container about 30 cm taller than standard (2.69 m inside).
- Orientation
- Which side of the box faces up.
- Payload
- Maximum cargo weight a container may carry.
Frequently asked questions
How many 50 × 40 × 30 cm boxes fit in a 20 ft container?
Kept upright, a mixed floor pattern of 64 per layer and 7 layers gives 448. If boxes may be turned, 109 per layer standing on the 50 cm side × 4 layers plus 64 laid flat in the gap above gives 500.
How do I calculate how many boxes fit in a container?
Divide each container side by a box side (rounding down) for each orientation and multiply; the best orientation wins.
Why is the volume-only number higher?
It assumes boxes can fill every corner; leftover strips along the walls are always wasted.
What are the inside dimensions of a 40 ft container?
About 12.03 × 2.35 × 2.39 m (67.6 m³); a high cube is 2.69 m tall (76 m³).
What is a pallet-wide container?
A container about 2.44 m wide inside, so two Euro pallets fit side by side.
How much weight can a container carry?
Roughly 25–28 t of payload; check the CSC plate and road limits in your country.
Can I mix box sizes?
This calculator handles identical boxes; for mixed loads plan each size separately.