Corrugated Board GSM by Ply: 3, 5 and 7 Ply Grammage
The typical GSM of 3 ply corrugated board is about 420 g/sqm. That is the combined weight of both flat liners and the single fluted layer, per square metre. 3 ply is single wall, the lightest of the common grades, and it suits light parcels shipped on a single haul.
What is the typical GSM of 3 ply corrugated board?
The typical GSM of 3 ply corrugated board is about 420 g/sqm. This is the combined grammage: the weight of both liners plus the fluted middle layer, measured per square metre. 3 ply is single wall, the lightest common grade. For a buyer it reads as one number that sums the whole board, not any single sheet.
GSM stands for grams per square metre. When you see about 420 on a 3 ply spec, that figure already adds up both flat liners and the fluted layer glued between them. You do not stack three separate numbers. One combined figure describes the board you actually ship in. Single wall means one flute, so 3 ply carries the least paper of the grades sold for parcels, which is why it prices the lowest per box.
Read a board spec in four quick checks:
- Ply: 3 ply is single wall, one flute between two liners.
- Combined GSM: about 420 g/sqm for 3 ply, the whole board, not one sheet.
- Flute: a single flute, E, B or C, sets the thickness and the print surface.
- Fit: light goods on a single haul are where 3 ply earns its place.
How much does 5 ply and 7 ply board weigh per square metre?
5 ply board weighs about 700 g/sqm and 7 ply about 980 g/sqm, both as combined grammage. 5 ply is double wall: two flutes and three liners. 7 ply is triple wall: three flutes and four liners. Each step up adds paper, crush resistance and cost, so heavier grammage tracks heavier, more protective board.
The pattern is steady. More walls mean more paper, and more paper means a higher combined GSM. 5 ply carries roughly two-thirds more board than 3 ply, and 7 ply adds more again. 5 ply suits heavier or fragile goods and stacked loads. 7 ply is a freight and export grade, more box than a normal parcel needs. The table sets the three grades side by side on the figures a buyer weighs.
| Ply | Combined board | Walls | Flute grade | Typical use |
|---|---|---|---|---|
| 3 ply | about 420 g/sqm | Single wall | Single flute: E 1.5mm, B 3mm or C 4mm | Light parcels, apparel, cosmetics, sub-5 kg goods |
| 5 ply | about 700 g/sqm | Double wall | BC combination, about 7mm | Heavier or fragile goods, stacked or long-haul loads |
| 7 ply | about 980 g/sqm | Triple wall | Three flutes for heavy freight | Heavy parts, bulk export cartons, rough long hauls |
These are typical values, not fixed constants, because recycled kraft varies with the batch. The grammage figure is verified against the target for the ply so the board weighs what the spec says it should.
Why does GSM matter more than ply alone?
Ply tells you how many walls the board has. GSM tells you how much paper is actually in those walls. Two boxes can both be 3 ply and still differ in strength if one runs less grammage than it claims. Combined GSM, verified against the target, is the honest measure of what you are buying.
Ply alone can mislead. A supplier can call board 3 ply while running thin liners that fall short of about 420 g/sqm. The box looks right and behaves wrong under load. This is why Vikrama Industries verifies GSM against the target for the ply and burst-tests each batch, so the grammage on the spec is the grammage in your hands. A physical sample is approved before any run.
Ply counts the walls. GSM weighs the paper inside them. The second number is the one that protects your product.
So when you compare two quotes, do not stop at the ply. Ask for the combined GSM and whether it is verified. Same ply, lower grammage, weaker box. The number on the spec only helps when someone checks the board against it.
How does board weight change the box price?
Board weight is the main price driver. Corrugated is sold largely by the paper in it, so higher grammage costs more per box. Moving from about 420 g/sqm at 3 ply to about 700 at 5 ply adds roughly two-thirds more board, and the per-box estimate rises with it. Heavier grade, heavier paper, higher price.
Take one common size, 12 x 10 x 6 inches, plain and unprinted, at a run of 1000. The worked bands below show how the grammage step moves the per-box figure. These are example bands, not fixed quotes, because the kraft paper rate is a market band that moves with mill supply and demand.
| Ply | Combined GSM | Per-box estimate band |
|---|---|---|
| 3 ply | about 420 g/sqm | about ₹12.78 to ₹17.66 |
| 5 ply | about 700 g/sqm | about ₹21.29 to ₹29.44 |
So the same box in 5 ply lands roughly Rs 8 to Rs 12 higher per unit at this size and quantity. Over 1000 boxes that is real money, which is why you match the grade to the load and do not pay for wall you do not need. When the product is heavy or the boxes stack, the heavier grammage is cheaper than a round of damaged returns.
The 5 ply premium on a 12 x 10 x 6 box is roughly Rs 8 to Rs 12 a unit, set almost entirely by the extra grammage.
Prices attract 5% GST (HSN 4819); a GST invoice is issued with every order. Your confirmed figure comes back on WhatsApp usually in minutes, always within 24 hours, after a person checks the day's paper rate and the exact allowances for your size.
Frequently asked questions
What is the GSM of 3 ply corrugated board?
About 420 g/sqm. That is the combined grammage, adding both flat liners and the single fluted layer per square metre, not any one sheet. 3 ply is single wall, the lightest common grade, and it suits light goods shipped on a single haul. The figure is verified against the target for the ply so the board weighs what the spec says.
Is higher GSM always better?
No. Higher GSM means more paper, more strength and more cost. If your product is light and ships in a single haul, about 420 g/sqm at 3 ply protects it and prices lower, so paying for 5 ply at about 700 is paying for board you do not use. Match the grammage to the load, not the other way round.
Does GSM or ply decide box strength?
Both, but GSM is the honest measure. Ply counts the walls; GSM weighs the paper in them. Two boxes can share a ply and differ in strength if one runs thin liners below its target grammage. Verified combined GSM, plus a batch burst test, is how you know the board matches its spec before it becomes your parcels.
How much more does higher GSM board cost?
On a 12 x 10 x 6 inch box at 1000 units, plain, 3 ply at about 420 g/sqm works out to roughly Rs 12.78 to Rs 17.66, and 5 ply at about 700 to roughly Rs 21.29 to Rs 29.44 per unit. That is about Rs 8 to Rs 12 more per box. Bands move with the kraft paper rate, so a person confirms your exact figure before any run.