Carton Optimisation: The Cheapest Freight Saving Nobody Asks For

The real numbers, same product family

Compare two rectangular 750 ml containers from the same catalogue:

Half a centimetre on each dimension buys 9,900 extra pieces per container. Nothing about the product changed.

The same effect in the thickened rectangular series:

One centimetre of carton height costs 5,400 pieces. Scale that across a year of shipments and it is a full container.

Why carton dimensions drift

Cartons are sized to the container, not to the pallet or the container ship. Four things push them larger than necessary:

1. Lid clearance. A carton must clear the lid stack; a 3 mm allowance becomes 10 mm "for safety".
2. Insert or divider. Added for breakage, sometimes unnecessary.
3. Hand-packing tolerance. A carton designed for a machine is tighter than one packed by hand.
4. Reused carton sizes. Factories standardise on a few carton sizes to simplify purchasing, which forces the product into an oversized box.

None of these is wrong. All of them cost the buyer money, and none of them is visible on a quotation.

What to ask for

Three figures per SKU, every time:

Then compute pieces per m³ yourself and compare across suppliers. It is the only apples-to-apples freight metric. Two quotes at the same FOB price can differ 5% in landed cost on this alone.

The pallet dimension

A 40HQ floor is 12.03 × 2.35 m. Standard pallets are 1.2 × 1.0 m or 1.2 × 0.8 m.

• With 1.2×1.0 m pallets: 2 across, 10 deep = 20 pallets, using 2.35 m of a 2.35 m width — no waste
• With 1.2×0.8 m pallets: 2 across with a 0.75 m gap, or 3 across at 2.4 m — which does not fit

A carton sized to 1.2×1.0 m pallets eliminates that gap. A carton at 52.5×25 cm fits a 1.2 m pallet in two rows of 4 with 5 cm spare — nearly ideal. A 74×25 cm carton (the GG3000 series) fits only one row, wasting 46 cm of pallet width per layer.

Where optimisation stops

You cannot shrink a carton past the product. Three hard limits:

• Rim protection. The carton must clear the rim; crushing the top layer is worse than the 2% you save.
• Stack strength. A shorter carton stacks higher, which increases bottom-layer compression. The savings can reverse into a damage claim.
• Hand-pack speed. Tighter cartons slow packing, and the labour cost can exceed the freight saving on small runs.

The realistic target is 2–4% more pieces per container, not 10%.

FAQ

Can I ask a supplier to resize a carton? Yes, but it usually needs a new carton print plate and a new packing trial. Budget for a one-off cost and expect a minimum run.

Does a smaller carton increase damage? Only if it reduces the clearance below what the rim needs. A well-fitted carton protects better than an oversized one, because the product cannot shift.

Is floor loading better than pallets for PP? Floor loading gains 10–15% volume. It also removes the pallet's load-spreading effect and increases compression on the bottom layer. For cartons above 7 kg, pallets are safer.

How do I compare two quotes properly? Convert both to landed cost per 1,000 pieces, using carton CBM, pieces per carton and the freight rate. Anything else is a comparison of FOB prices, which is not the number that matters.

Related reading

• LCL vs 20GP vs 40HQ: Choosing the Right Load
• 750ml PP Food Container: 9 Models Compared
• ml to oz: PP Food Container Capacity Chart

Models covered on this site: 750 ml PF-418 · 750 ml PF-L750 · 750 ml PF-RG750 · see all models in this category.