Unit Price Comparison

How to use the unit price comparison

1. Fill in the fields — they start with a worked example.
2. Read the answer, and the arithmetic shown beneath it.
3. Copy the results, or adjust the inputs to compare scenarios.

About this tool

Shops price in packs; value lives in the unit. Comparing 750 g at one price against 1.2 kg at another is arithmetic nobody wants to do in an aisle, and it is the arithmetic that decides which is cheaper.

Enter each option's price and size in the same unit — grams against grams, millilitres against millilitres — and the cheapest per unit is identified along with how much more the others cost.

Bigger is not automatically better value. Multi-buys and larger packs are frequently more expensive per unit than the standard size, which is exactly what this makes visible.

Common uses

• Deciding between pack sizes in a shop.
• Checking whether a multi-buy is really cheaper.
• Comparing subscription tiers by unit.

Frequently asked questions

Do the units have to match?

Yes. Compare grams with grams or millilitres with millilitres. Convert first if one is in kilograms and another in grams.

Is the bigger pack always cheaper per unit?

No, and that assumption is what retailers rely on. Larger packs are often priced above the smaller ones per unit.