Which One Is the Better Deal?

Package sizes vary widely — a 32 oz bottle and a 16 oz bottle of the same product can look similar on the shelf, but one costs twice as much per ounce. The sticker price tells you what you'll spend at the register; the unit price tells you what you're actually getting for your money. Comparing unit prices is the only reliable way to know which product is the better deal, regardless of package size.

You can't directly compare a volume measurement (fl oz, ml, liters) to a weight measurement (grams, oz, pounds) — they measure different things. For most grocery comparisons, stick to the same type: compare both products by weight, or both by volume. The calculator will warn you if you mix unit types.

Usually, but not always. Warehouse stores like Costco typically offer lower per-unit prices on staples like paper goods, nuts, and cooking oil. But some bulk prices are surprisingly close to — or even higher than — grocery store sale prices. The only way to know for certain is to run the numbers.

Use "count" when items are sold by the piece rather than by weight or volume — things like eggs, batteries, tea bags, vitamin capsules, or paper plates. If a 40-count pack costs $6.99 and a 100-count pack costs $14.99, selecting "count" for both lets the calculator tell you the price per individual item.

They shouldn't — the calculator saves your inputs automatically using your browser's local storage. If your numbers disappeared, it's likely because your browser's privacy settings clear local storage on exit, or you're using private/incognito mode, which doesn't save local storage between sessions.

Yes — click the "+ Add Another Product" button to add up to four products. The results will rank all of them from best to worst deal, show the price per unit for each, and calculate how much cheaper the best option is compared to the most expensive.