How to Check a Smaller Package at the Same Price
A same shelf price can still mean a higher unit price when the new package is smaller. The price tag looks unchanged, but each ounce, sheet, serving, or unit can cost more.
Use the shrinkflation calculator to enter the old package and new package values, then compare the old and new unit prices.
The Simple Formula
unit price = price / package size
unit price increase = (new unit price - old unit price) / old unit price
When the shelf price stays the same but the package size falls, the unit price rises because the same money buys less product.
Generic Example
This example uses made-up package values only, so it stays evergreen and does not depend on a named product.
| Version | Price | Package size | Unit price | What changed |
|---|---|---|---|---|
| Old package | $2.00 | 16 oz | $0.1250 per oz | Baseline package |
| New package | $2.00 | 12 oz | $0.1667 per oz | Same price, smaller size |
In this example, the package is 25% smaller, while the unit price rises by about 33.3%.
Common Traps
- Same price smaller size: compare the unit price, not just the shelf price.
- Unit changes: compare ounces with ounces, fluid ounces with fluid ounces, and counts with counts.
- Count changes: fewer sheets, servings, loads, or units can raise the real price.
- Multipacks: compare total amount across the full pack.
- Sale labels: use the final price you are actually comparing.
Related calculators
Next guide
If the package size and price both changed, compare the old and new unit prices directly.