How the comparison works
Each size is converted to a standard unit (kilograms for weight, litres for volume, or single pieces). The price is then divided by that amount. The product with the lowest price per unit is the best value, and the others show how much more you pay for the same amount.
Shopping tips
- Check the unit price on the shelf label too. Some shops print it.
- Only buy a big pack if you will really use it.
- Combine this with a coupon: work out the final price with the discount calculator, then compare the unit price again.
Need to convert between kg, lb or oz first? Use the unit converter.
Frequently asked questions
What is unit price?
The price of one standard amount, such as 1 kg, 1 litre or 1 piece. It lets you compare packs of different sizes fairly.
Is the bigger pack always cheaper?
Not always. Sometimes the small pack is on offer or the large pack is priced higher per kg. That is why checking the unit price is worth it.
Can I compare different units, like g and kg?
Yes, as long as they measure the same kind of thing. Grams and kilograms are both weight, millilitres and litres are both volume. You cannot compare weight with volume.
How many products can I compare?
Up to four. Leave a product blank to skip it. You need at least two.
Do I need to think about quality?
Yes. The cheapest per kg is not always the best buy: consider quality, shelf life and whether you will use it all before it spoils.