How Does It Work?
- Pick what you are comparingWeight, volume or a plain count. This sets the units available on each row and the basis the comparison is shown in.
- Enter each optionPrice and size for up to four packages. Mix units freely — 500 g against 1 kg, or 330 ml against 2 L — because everything is converted to a common base.
- Read the per-unit columnPrices per 100 g, per 100 ml or per item, with the cheapest highlighted and the others shown as a percentage more expensive.
What Is It Used For?
Shelf labels are supposed to show a unit price, but they are inconsistent, sometimes missing, and frequently in a different base between two products sitting side by side — one per 100 g, the next per kilogram. Larger packs are also not automatically cheaper: multi-buys and "value" sizes regularly work out dearer per unit than the standard pack, which is exactly what this makes visible in a couple of seconds.
- Deciding whether the big box is genuinely better value than two small ones.
- Comparing products whose shelf labels use different unit bases.
- Checking whether a multi-buy offer actually beats the single-item price.
- Comparing an online price against an in-store one at a different pack size.
- Working out cost per portion when planning a meal or an event.
Examples
| Option A | Option B | Per 100 g | Cheaper |
|---|---|---|---|
| 2.49 for 500 g | 4.29 for 1 kg | 0.50 vs 0.43 | B by 16% |
| 1.20 for 250 g | 2.10 for 500 g | 0.48 vs 0.42 | B by 14% |
| 3.00 for 1 kg | 1.40 for 400 g | 0.30 vs 0.35 | A by 17% |
| 5.00 for 6 items | 9.00 for 12 items | 0.83 vs 0.75 each | B by 11% |