What it works out, and when you need it
Shippers build pallets to a pattern: so many cartons a layer, so many layers, under a height and a weight. Forwarders quote by the pallet, and warehouses take pallets up to a height.
- It stands one carton size upright on the deck, both ways round, and keeps the way that fits more in a layer.
- It adds layers up to your height, and stops early if the weight would pass the pallet's safe working load or your own limit.
- The Euro pallet (EUR) is EPAL's (the European Pallet Association): 1200 × 800 mm, 144 mm high, about 25 kg, with a safe working load of 1,500 kg. The other sizes are in ISO 6780, the International Organization for Standardization's list of pallet sizes.
The formula
per layer = the larger of
(pallet L ÷ carton L) × (pallet W ÷ carton W)
(pallet L ÷ carton W) × (pallet W ÷ carton L)
layers = (height limit − pallet's own height) ÷ carton H
each division rounded down
cartons = per layer × layers,
no more than safe working load ÷ carton weight
loaded height = pallet's own + layers × carton H
loaded weight = pallet's own + cartons × carton weight
- With a weight limit of your own, the cartons stop at that limit less the pallet's own weight, if that comes first. The top layer may then be part full.
- An overhang lets cartons stand out past each edge of the deck by that much. It weakens them: in a Fibre Box Association study, 1 inch of overhang on one side cut a box's strength by 3.79% to 19.27%.
A worked example
The calculator starts with it.
- Cartons of 600 × 400 × 400 mm at 12 kg on a Euro pallet (EUR), 1,800 mm high at most.
- Per layer: 1,200 ÷ 600 = 2 by 800 ÷ 400 = 2: 4 cartons. Turned: 1,200 ÷ 400 = 3 by 800 ÷ 600 = 1: 3. So 4.
- Layers: (1,800 − 144) ÷ 400 = 4.14, so 4.
- 16 cartons, 144 + 4 × 400 = 1,744 mm high, 25 + 16 × 12 = 217 kg: well under the 1,500 kg safe working load.
- In a 20 ft container (20' GP, general purpose): 11 pallets on the floor, 176 cartons. Two tiers would need 3,488 mm, more than the 2,292 mm door. The same cartons loose: 225.
Standard pallet sizes
The sizes the calculator offers: the Euro pallet from EPAL, the others from ISO 6780. Choose one above, or type your own.
| Pallet | Size (mm) | Size (inches) | Used most in |
|---|---|---|---|
| Euro pallet (EUR, EPAL) | 1,200 × 800 mm | 47.2 × 31.5 in | Europe |
| ISO pallet | 1,200 × 1,000 mm | 47.2 × 39.4 in | Europe and Asia |
| US pallet | 1,219.2 × 1,016 mm | 48 × 40 in | North America |
| Square pallet | 1,100 × 1,100 mm | 43.3 × 43.3 in | Asia |
| Square pallet | 1,165 × 1,165 mm | 45.9 × 45.9 in | Australia |