Container Loading Calculator (3D Box Packing)
Plan 3D box packing into 20ft, 40ft, and 40ft High Cube containers with payload and volume utilization.
Live Calculation Results
Containers required & pieces loaded
20 ft standard dry · 278 pieces loaded per container · 1,500 total order
- Containers required
- 6 containersPlanning estimate: ⌈1,500 order pieces ÷ 278 loaded/container⌉
- Pieces loaded (1 container)
- 278 of 1,500278 pieces packed in this container
- Total order quantity
- 1,500Total pieces in your shipment order
- Remaining quantity
- 1,222Unloaded after 1st container
- Recommended capacity
- 278Capacity under payload/dimensional constraints (geometric fit 278 pieces)
- Geometric capacity
- 278Theoretical 3D packing capacity before payload or order quantity constraints
- Cube utilization
- 80.5%Cargo volume ÷ internal container volume
- Weight loaded
- 4,170.00 kg14.8% of payload limit
- Unused volume
- 6.47 m³
- Layers
- 5
- Loaded length used
- 5,800 mm
What this means
- This arrangement loads 278 pieces into one 20 ft standard dry from a total order of 1,500 pieces (1,222 remaining after the first container).
- Based on packing 278 pieces per container, approximately 6 containers will be required to ship the full order (planning estimate based on selected equipment and packing assumptions; real-world loading may vary with dunnage, axle weight limits, and weight distribution).
- Recommended capacity is 278 pieces per container under payload and dimensional constraints (geometric capacity is 278 pieces).
- Height is limiting: unused height remains, but not enough for another layer.
- The payload limit would allow 1,880 pieces, so weight is not the constraint here.
Colours show different carton orientations. Drawn from the calculated coordinates.
5 layers. Identical items behind each other are drawn once.
Assumptions used
- 20 ft standard dry: reference specification. Ocean container lines (reference: Maersk dry container specifications); reference check 2026-10-06 (secondary cross-check). Reference ISO dry freight container. ISO 668 rating: 30,480 kg max gross. Door openings typically 2,340 mm W × 2,274–2,280 mm H. Actual payload depends on unit tare stamped on door plate.
- Containers required = ⌈Total Order Quantity ÷ Pieces Loaded per Container⌉. This is a planning result based on the selected equipment and deterministic packing assumptions; actual real-world loading across multiple containers may vary due to weight distribution, dunnage, bracing, and cargo securing.
- Recommended capacity defines the maximum feasible pieces per container constrained by both 3D interior geometry and equipment payload limits.
- Layer-based 3D packing of identical rectangular pieces: each layer is a 2D floor packing; layers of different orientations can be combined. No randomness, same input gives the same result.
- This is the best tested arrangement, not a proof of the global optimum. Real loading needs bracing, dunnage and weight distribution.
- REFERENCE EQUIPMENT SPECIFICATION: Actual equipment dimensions, tare weights, and payload ratings vary by manufacturer, container build year, and ocean line. Always inspect the CSC safety approval plate on the physical container provided for your shipment.
Container dimensions and what varies →Loading pallets instead of loose cartons? →
Planning Notice & Scope Boundary
Container specifications vary by manufacturer and steamship line. Check the CSC plate on your container.
Formula & Calculation Methodology
Deterministic 3D rectangular layer and strip packing algorithm. Enforces container internal dimensions, door openings, cargo payload, and orientation limits.
Cube Utilization = (Boxes Loaded * Box Volume) / Container Volume| Variable | Definition & Basis |
|---|---|
| Boxes Loaded | Actual count placed without overlap within boundary constraints |
| Payload kg | Total gross weight vs maximum permitted equipment payload |
| Cube Util % | Ratio of cargo volume to interior container volume |
Worked Example: Loading 20ft Dry Container with Export Cartons
Packing 500 × 400 × 300 mm cartons weighing 15 kg each into a standard 20ft container (5896 × 2350 × 2393 mm, 28,200 kg payload).
Input Parameters
- Carton Dims500 × 400 × 300 mm, 15 kg each
- Equipment20 ft standard (internal 5.89 × 2.35 × 2.39 m)
- Target Order Qty600 cartons
Step-by-Step Calculation Breakdown
- 1Test candidate layer heights (300, 400, 500 mm).
- 2In upright orientation (height = 300 mm), container height 2393 mm accommodates 7 layers.
- 3Floor packing places 27 cartons per layer.
- 4Total cartons packed: 27 × 7 = 189 cartons (tested multi-orientation fills to capacity).
- 5Payload verified: 189 × 15 kg = 2,835 kg (well below 28,200 kg payload limit).
Assumptions Used
- Boxes are rigid rectangular cuboids placed along orthogonal Cartesian axes.
- Equipment specifications represent standard reference dry containers (CSC plate specs).
- Non-random, deterministic heuristic evaluation prioritizing constraint safety.
Important Limitations
- Represents best tested arrangement found; not a mathematical global optimum.
- Real container loading requires allowance for dunnage, air bags, floor lashing, and door sill clearance.
Authoritative Standards & Sources
Dry container reference specifications — 20 ft, 40 ft and 40 ft high cube ↗
Internal dimensions, door openings and approximate payloads were taken as representative planning figures. Carriers publish slightly different values per equipment type and manufacturer.
Frequently Asked Questions
What is the difference between a 40ft standard and 40ft High Cube container?
Both have the same length (12.03 m) and width (2.35 m), but a 40ft High Cube is 1 foot (30 cm) taller inside (2.70 m vs 2.39 m), providing ~76 CBM of volume versus ~67 CBM.
Why doesn’t carton volume divide evenly into container volume?
Carton geometry and physical orientation prevent 100% space filling. Gaps between cartons and roof clearance typically limit real-world cubic utilization to 80–88%.
Can I exceed the container payload if there is still space inside?
Never. Exceeding maximum payload violates SOLAS VGM regulations, damages equipment, and risks port rejection or severe fines.
What to Calculate Next
Freight planning connects sequentially from package dimensions to freight class, pallets, and full equipment: