The dimensions are remarkably consistent across brands and countries, because the carton is sized around the pack, and the pack is sized around the cigarette.
The numbers
A US carton is roughly 5½ × 3½ × 2½ inches — about 14 × 9 × 6 cm. It weighs a little over half a pound, or around 250 grams.
That is small enough to hold in one hand and heavy enough to feel substantial. Ten cartons fit in a modest shipping box.
Why it is that size
Ten packs, arranged two by five. Each pack holds twenty cigarettes in three rows, wrapped in foil-lined card. The carton is sized to the pack block with no wasted space, which is why cartons stack efficiently and why the dimensions do not vary much.
Variations
Slim and super-slim cartons are narrower, because the packs are narrower. Japanese cartons are slimmer than US cartons of the same count for the same reason — Japanese packs are narrower.
A carton of 100s is slightly longer than a carton of kings, by the difference in cigarette length.
Storage implications
Small footprint, easy to store. A cupboard shelf holds a dozen cartons without difficulty. Keep them out of sunlight and away from heat sources — see storage.
Do not stack heavy objects on top. Cartons deform, and a crushed carton can crack the foil on the end packs.
Shipping implications
A carton is an efficient shipping unit: dense, rectangular, already sealed in cellophane. That is why online tobacco sells by the carton and almost never by the pack — the packaging cost of a single pack exceeds the margin.
Our packing note covers how parcels are assembled.
What it is not
It is not the cardboard box your order arrives in. That is a shipping carton, a different object that happens to share the word — a distinction that causes real confusion in listings. Our definition piece covers the terminology.