Unit price calculator
Two products, two prices, two sizes: which costs less per unit?
Better value
Better value: B
- Price per unit, A
- US$0.0070
- Price per unit, B
- US$0.0060
- Cheaper per unit by
- ≈ 14.1834%
How it works
Divide each price by its quantity to get the price per unit. The lower unit price is the better value, provided you will use the larger amount.
Both quantities must be in the same unit. If one pack is in grams and the other in kilograms, convert first (1 kg = 1,000 g).
The saving shows how much less the cheaper option costs per unit, as a percentage of the dearer one.
Formula
Unit price = price ÷ quantity Saving = (higher − lower) ÷ higher × 100
Worked example
500 g for 3.49 is 0.00698 per gram; 1,000 g for 5.99 is 0.00599 per gram. The larger pack is cheaper per gram by (0.00698 − 0.00599) ÷ 0.00698 ≈ 14.18%.
Questions people ask
Is the bigger pack always cheaper?
No. Multi-buy offers and promotions on small packs often make them cheaper per unit, which is why comparing unit prices helps.
Why are unit prices shown with four decimals?
Prices per gram or millilitre are tiny, and two decimals would hide the difference. Multiply by 100 or 1,000 for a price per 100 g or per kg.