Packaging guide
How many pieces fit in a carton?
Carton quantity explained — what PCS/CTN means, how to work out how many pieces fit, the counts this market packs in, and the weight that caps them.
Published · Updated
In short
- Carton quantity is the number of pieces in one carton — written PCS/CTN or Qty/Ctn on a packing list.
- There is no standard. The packer chooses it to suit the product and the way buyers order.
- To work it out, divide each inside dimension of the carton by the piece, keep the whole number, and multiply the three.
- Try the piece in every orientation — the same carton can hold 60 one way and 64 another.
- Weight is the usual limit. Most master cartons stay under about 20 kg so one person can lift them.
What carton quantity means
Carton quantity is the number of sellable pieces in one carton. It goes by several names and all of them mean the same thing: pieces per carton, units per carton, pack size, and on a packing list or invoice, PCS/CTN or Qty/Ctn.
It sits in a row with the numbers every shipment document carries: the carton number, the pieces per carton, the total pieces, the gross and net weight, and the measurement in CBM. Get the carton quantity wrong and every other figure on the line is wrong with it.
There is no standard count
Nobody sets a rule for how many pieces go in a carton. The packer chooses the count, and a good one does three things at once: it fits the carton without gaps, it stays light enough to lift, and it matches how buyers order— a shopkeeper who buys by the dozen wants cartons of 12 or 24, not 17.
That is why the same few counts turn up across trades:
| Count | Where you see it |
|---|---|
| 6 · 12 | A half dozen and a dozen — inner boxes of glasses, cups, bottles and jars |
| 24 | Two dozen, four rows of six — soft-drink cans and bottled goods |
| 48 · 72 | Master cartons of inner boxes — glass tableware lists write (1 × 6) × 12 = 72 |
| 144 | A gross, twelve dozen — a counting unit in the match trade |
| 1,000 | Matchboxes, 10 × 10 × 10 — ten to a packet, ten packets to a bundle, ten bundles to a carton |
Two of these trades have their own pages: glassware and crockery boxes and matchbox master cartons.
How to work out how many fit
For a carton that already exists, measure it on the inside and measure one piece at its longest, widest and tallest points. Then for each direction:
A worked example
A carton measuring 17 × 12.5 × 10 inches inside, and a boxed product of 4 × 3 × 2.5 inches:
- Along the length — 17 ÷ 4 = 4.25, so 4
- Across the width — 12.5 ÷ 3 = 4.17, so 4
- Up the height — 10 ÷ 2.5 = 4
- Carton quantity — 4 × 4 × 4 = 64 pieces
Then turn the piece
The same product turned so its 3-inch side runs along the carton gives 17 ÷ 3 = 5, and 12.5 ÷ 4 = 3, and 10 ÷ 2.5 = 4 — 60 pieces. Four fewer, in the same carton, just from the orientation. A rectangular piece can face six ways; try the ones that make sense for the product (a jar should not travel on its side) and keep the best.
The leftover space matters too. In the first arrangement the pieces fill 16 of the 17 inches and 12 of the 12.5 — an inch spare one way and half an inch the other, enough to rattle. Either fill it with a pad, or better, size the carton to the count.
Better: choose the count, then size the carton
Working out what fits in a carton you already have is the second-best way round. If the carton is being made anyway, decide the count first — the one your buyers order in — and have the carton made to hold exactly that. No gaps, no rattling, and no paying freight on air.
The box size calculator does this: give it the piece and how many go along, across and up, and it returns the internal carton size to ask for.
Weight sets the ceiling
A carton can be big enough for 100 pieces and still be wrong at 100. What limits the count more often than size is weight: a master carton that one person cannot lift safely is the one that gets dropped, so most are kept under about 20 kg.
The weight also decides the board. A heavier count needs a stronger carton — see 3-ply, 5-ply or 7-ply, or put the weight into the ply and board grade selector.
Inner boxes change the sum
When pieces are boxed in inners first, the master carton quantity is two numbers multiplied: pieces per inner × inners per master. The master carton is then sized around the inners, not around the pieces — see what is a master carton?
A partition changes it too. The strips of board between the pieces take real space, so a carton that holds 24 loose will not hold 24 with a partition unless it was made for one. Say so when you enquire, and the carton and the partition are sized together.
Where to go next
- Carton CBM calculator — how much space the cartons will take in a truck or a container.
- How to measure a carton — inside versus outside, and the order the numbers go in.
Common questions
What does carton quantity mean?
Carton quantity is the number of sellable pieces packed in one carton. On a packing list or an invoice it is usually written PCS/CTN, Qty/Ctn or units per carton. Multiply it by the number of cartons and you have the total pieces in the shipment.
Is there a standard number of pieces per carton?
No. The carton quantity is chosen by whoever packs the goods, to suit the product, the carton and the way buyers order. Counts that divide into how a trade buys — 6, 10, 12, 24, 48, a dozen or a gross — are common because they make ordering and counting easy, not because any rule requires them.
How do I calculate how many pieces fit in a carton?
Divide each inside dimension of the carton by the matching dimension of one piece, keep only the whole number, and multiply the three results. A carton 17 × 12.5 × 10 inches inside holds pieces of 4 × 3 × 2.5 inches four along, four across and four high — 64. Then turn the piece and try again, because a different orientation can fit more or fewer.
How many cans are in a carton?
It depends on the packer. In Pakistani shops, 250 ml soft-drink cans are sold both in cartons of 24 — four rows of six — and in packs of 12. The count is chosen so the cans tile the carton base with no gaps, and a partition or a tray may sit between layers.
What is master carton quantity?
The total pieces in one master carton: the pieces in each inner box multiplied by the number of inner boxes. Glass tableware makers write it as a formula — (1 × 6) × 12 = 72 means six glasses to an inner box and twelve inners to the master, so 72 glasses. If there are no inner boxes, it is simply the pieces in the carton.
What limits how many pieces go in one carton?
Weight, more often than size. A carton that one person cannot lift safely is the one that gets dropped, so most master cartons are kept under about 20 kg. Multiply the weight of one piece by the count, add the carton, and if the total is too heavy, lower the count or split it into two cartons.
