Unit Price Comparator
Bigger packs are usually better value, and the exception is common enough to be worth checking every time. Comparing properly means dividing price by size for each option — easy arithmetic that is genuinely hard to do in your head across four packs in three different sizes. This ranks them and says plainly whether the largest is actually the best buy.
What this generator does
Divides each pack's price by its size to get a directly comparable unit price, ranks them from best to worst value, and reports how much dearer the worst is than the best along with whether the largest pack won.
How to use this tool
- Choose how many products to compare.
- Read the price per 100 units — that is the only fair comparison.
- Check the ranking, then whether the biggest pack came first.
- Note the spread: the difference between best and worst is often surprising.
Understanding the controls
- How many products
- Between 2 and 6 packs at varying sizes and prices. Some are deliberately generated so the largest is not the best value, because that is the case worth catching.
- Seed
- Any word reproduces exactly the same packs and prices.
Common use cases
- Comparing supermarket pack sizes properly
- Checking whether a multi-buy is actually cheaper
- Teaching unit rates with a genuinely useful application
- Settling whether the big box is worth it
- Setting the same comparison twice from a seed
How this generator works
The check verifies more than the arithmetic: it confirms the ranking is genuinely consistent with the unit prices, that the pack named cheapest really does have the lowest, and that the verdict about the largest pack matches the sizes. Those could each be wrong independently, so each is checked separately.
Randomness and fairness
The pack sizes and prices are random, deliberately including cases where the largest is not the best value. A seed reproduces the same comparison exactly and is therefore explicitly not cryptographically secure. Without a seed the browser's cryptographically secure generator is used.
For how randomness is produced across the whole site, see how Generate Random works.
Limitations and good to know
- Compares price against size only. Quality, waste, whether you will use it before it spoils, and the cost of storing it are all real and none is modelled.
- Packs are generated rather than entered from real products.
- A single unit type per comparison — comparing by weight against by count is not meaningful and is not offered.
- Multi-buy offers and loyalty pricing are not modelled.
- Comparisons are not stored between visits; seed one you want again.
Privacy and your data
The comparison runs entirely in your browser. Nothing about the packs or your seed is transmitted or kept.
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