The price did not go up. The bag got smaller.
Shrinkflation is a price rise disguised as a package redesign. Statisticians catch it, shoppers mostly do not, and there is a reason companies prefer it.
You know the feeling before you can name it. The bag looks the same. The price is the same. Something is wrong with the bag.
You are usually right. The chocolate bar lost a segment. The crisp packet holds more air. The tub of ice cream that was a litre is now nine hundred millilitres and has a subtly different base so it still fills the same space in the freezer.
This is shrinkflation. That companies do it is the boring half. The interesting half is why they prefer it to raising the price, and what that preference reveals about how you actually shop.
The reason it beats a price rise
Consider a manufacturer facing higher input costs who needs an extra ten percent of revenue per unit. Two options.
Raise the price by ten percent. The number on the shelf label changes, and nothing in a shop is more visible than that. Shoppers notice immediately, price-comparison engines notice, competitors' labels sit right beside yours, and a segment of customers switch on the spot.
Or cut the contents by ten percent and leave the price alone. Now the shelf label is unchanged. The only place the change appears is the net weight, printed small, in a unit most people are not converting in their heads while holding a basket.
Both achieve the same revenue. Only one of them is legible at a glance. The research here is consistent, and unsurprising: people are markedly more sensitive to a change in price than to an equivalent change in quantity.
The inflation statistics do catch it
One belief worth correcting, because it circulates constantly: shrinkflation does not hide from the official inflation figures.
National statistical agencies collect prices *and* package sizes. When a size changes, they apply a quantity adjustment, so that the index measures the price per unit rather than the price per pack. A bar that shrinks by a tenth at an unchanged price is recorded as a price rise of roughly a ninth. This is standard practice at every serious statistics office.
So if you feel that official inflation understates your experience, shrinkflation is not the mechanism. The likelier explanations are duller. Your personal basket is weighted differently from the national one. Food and energy have risen faster than the all-items index, while occupying more of your budget than the average household's. Or you are comparing a receipt against a memory, and memories of prices sit years out of date.
Its quieter cousins
Shrinkflation has two relatives that behave the same way and get discussed less.
Skimpflation is the same manoeuvre applied to quality rather than quantity. The pack is the same size and the recipe is cheaper: less of the expensive ingredient, a cheaper oil, a substitution that survives most palates. Or, in services, the same price for a thinner version of the thing: fewer staff on the floor, a longer wait, a support line that has become a form.
Fee unbundling takes something that used to be included and charges for it separately. The headline price falls or holds while the total paid rises. Airlines industrialised this, and it has since spread to hotels, ticketing, food delivery and banking.
All three exist for the same reason. Each one moves cost from the number the customer compares to a number the customer does not.
How to see it
The defence is unglamorous and it works.
- Read the unit price, not the price. Most supermarkets are required to display price per kilo, per litre or per hundred grams on the shelf label. It is the small line under the big one, and it is the only number on the label that permits comparison.
- Compare by unit price across brands and pack sizes. The larger pack is not reliably cheaper per unit; promotional pricing frequently reverses it.
- Watch for a redesign. A new pack shape or a refreshed logo on a familiar product is often the moment the contents changed, because the redesign is what stops you noticing the old pack beside it.
- Check the net weight on things you buy weekly. These are the products where a small change compounds across a year, and the ones whose old weight you have some chance of remembering.
Why this site prices in fixed units
Every item in this game is quoted in a unit that cannot shrink. A litre of milk. A dozen eggs. A kilo of apples. One litre of fuel. A cup of coffee. One burger to a fixed specification.
That is deliberate, and it is the only way a cross-country comparison survives contact with packaging. Countries do not agree on pack sizes; the standard bottle, carton and bag differ everywhere. A price per pack would compare a Japanese carton against an American gallon, then call the result a fact about milk.
Normalising to a fixed unit costs some realism, because nobody buys exactly one kilo of apples. It buys something worth more: a number that means the same thing in every row of the table, and that will still mean the same thing when the packaging changes again.
Sources
More guides
- How to compare two countries without fooling yourselfCost-of-living comparisons go wrong in the same six ways every time. What follows is a method that survives contact with a real decision.
- Eggs are the most honest price in the shopNo brand, no marketing, barely any processing. When the egg price moves, something real happened to the birds, and everyone finds out at once.
- The exchange rate you looked up is not the one you were chargedBetween the rate on your screen and the number on your statement sit three separate margins, one of which you are invited to accept by a card machine abroad.
- A fifth of what you paid was tax, and you never saw the lineConsumption tax is the largest single wedge between two countries' prices for an identical product, and the one shoppers are least able to see.