Free tool
Ply and board grade selector
Say what the load weighs and where it is going. This shows which ply and which board grade are typically used for it — a starting point for a conversation, not a specification.
Published · Updated
In short
- Ply counts the paper layers: 3-ply is single wall, 5-ply double, 7-ply triple.
- Weight points at a ply. GSM and BF describe the paper, and decide how much that ply is really worth.
- These are typical ranges seen in this market, not a standard. Mills vary.
- Stacking height and journey length move the answer as much as weight does.
- Nothing we quote is specified from a table — it is specified against your load, and the specification is free.
Find the starting point
Weight suggests the construction; what the carton is for suggests the paper. Both matter, and they are answered together rather than one after the other.
Typically used for this
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- Typical liner GSM
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- Typical BF
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- Commonly used for
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Typical ranges seen in this market, not a standard, and not a specification. Mills vary, and the right grade depends on the load, the stacking height and the journey.
Send this with your enquiry:
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Get it specified properlyThe ply table in full
These are typical ranges, not guarantees. They are a starting point for a conversation, and any carton we quote is specified against your actual load rather than against a table.
| Construction | Also called | Typical load | Commonly used for |
|---|---|---|---|
| 3-ply | Single wall | 4–15 kg | Retail, e-commerce, courier, inner packs |
| 5-ply | Double wall | 20–45 kg | Heavier goods, stacking, ration and bulk packs |
| 7-ply | Triple wall | 45 kg and above | Industrial, machinery, export in place of a crate |
The board grade table in full
GSM is the weight of a square metre of the paper; BF is how strong that paper is. Two cartons of the same ply can perform very differently, and this is most of why.
| Application | Typical liner GSM | Typical BF |
|---|---|---|
| Light retail cartons, inner packs | 100–140 | 14–18 |
| E-commerce and courier boxes | 120–150 | 16–20 |
| Heavier goods, stacked storage | 150–180 | 18–22 |
| Export and industrial loads | 180+ | 20+ |
Why weight alone is a poor specification
A carton rarely fails because the contents were heavy. It fails because it was stacked six high in a warehouse for three weeks in humid air, or because it was handled at four different depots on the way south. Corrugated board loses a meaningful share of its stacking strength as it absorbs moisture, and it loses more the longer it is under load.
That is why this tool asks how the carton is stored and moved, and why the answer moves up a band when it is stacked. It is also why the honest version of this page ends by telling you to describe the journey rather than to trust the table. GSM and BF explained covers what those two numbers can and cannot tell you, and 3-ply, 5-ply or 7-ply covers what moves the load figures.
Common questions
Is this a specification I can order from?
No. It tells you which ply and board grade are typically used for a load like yours, so you know roughly what you are asking for and what it should cost to make. Any carton we quote is specified against your actual load, stacking height and journey rather than against a table — and that specification is free.
What does the ply number actually count?
The number of paper layers in the board. 3-ply is two liners with one fluted medium between them, 5-ply adds a second flute and a middle liner, 7-ply adds a third. More plies means more stiffness and more crush resistance, and also more board, more weight and more cost.
My load is between the bands. What now?
That is a genuine gap in the published ranges rather than a fault in the tool, and it is where the answer depends on things a weight alone cannot tell you — how the load is distributed, how high it stacks, how far it travels and how it is handled. Tell us what you are packing and we will specify it properly.
Can a stronger board let me use fewer plies?
Often, yes. A 3-ply carton in a high-BF board can outperform a 5-ply carton in a weak one, which is why ply on its own is a poor specification. GSM and BF describe the paper the board is made from, and the two questions are answered together rather than one after the other.
Why do you not use ECT or FEFCO codes?
They are North American and European standards. This market specifies in ply, GSM, BF and bursting strength in kg/cm², and quoting a code nobody here uses makes a specification harder to check rather than easier.
Does stacking change the answer?
A great deal. A box carries its own contents easily and the weight of everything stacked on top of it much less easily, so warehouse storage and tall pallets push the requirement up beyond what the contents alone suggest. Tell us how high they stack and for how long.
