How to compare unit prices
- Choose whether the products are sold by weight, volume or count (rolls, capsules, washing loads).
- For each product, enter the price, how many are in the pack and the size of each, with its unit. Mixed units are fine: grams against kilograms or ounces, millilitres against litres or gallons.
- The best value is highlighted in green and the verdict shows how much cheaper it is per kilo, litre or item.
Why unit prices matter
Pack sizes are designed to make comparison hard: 3 × 400 g for 6.50, 1 kg for 5.99 or 500 g for 3.49. Converting everything to a price per kilogram (or litre, or item) shows the true cost: here 5.42, 5.99 and 6.98 per kg, so the multipack is the best deal even though it costs the most at the till. Bigger is not always cheaper; promotions, store brands and "family size" packs can go either way, and shelf labels in some countries round or use different units for similar products.
Unit prices are especially useful for groceries, toiletries, detergent (compare price per wash), toilet paper (price per sheet or per metre), coffee, pet food and medicine. Remember that the cheapest per unit is only a saving if you will use it before it expires. Everything is calculated in your browser.
How do I calculate the price per unit?
Divide the price by the total quantity in a common unit: price ÷ (packs × size).
Can I compare grams and ounces?
Yes. Choose the unit for each product; everything is converted before comparing.
How do I compare toilet paper?
Choose Count and enter the number of sheets per roll as the size, so you compare price per sheet.