Price Per Weight Calculator
Find the true value of any product by converting its price and weight into a standardised cost per kilogram (and per lb / 100 g). Works for groceries, bulk goods, pet food — anything sold by weight.
Weight unit
Standardised cost per kilogram
- 1
Weight in grams
500 × 1 = 500 - 2
Price per gram
5.99 ÷ 500 = 0.01198 - 3
Price per kilogram
0.01198 × 1,000 = 11.98
How does this calculator work?
Price per kg = price ÷ weight in kg. For example, a 500 g bag at £5.99 costs £11.98/kg (£5.43/lb or £0.54/oz). Compare price per kg across pack sizes to find the best-value option regardless of quantity. Supports grams, kilograms, ounces and pounds.
Formula
How this is calculated
Supermarkets display a unit price on shelf labels (often per 100 g or per kg), but pack sizes vary and the label is sometimes missing or hard to read. This calculator converts any price and weight — in grams, kilograms, ounces or pounds — into a standardised cost per kilogram, per 100 g, per pound and per ounce, so you can compare two products directly regardless of pack size.
Internally all weights are converted to grams first using exact factors (1 kg = 1 000 g, 1 lb = 453.592 g, 1 oz = 28.350 g), then the per-gram price is scaled to each standard unit. The result is identical whichever input unit you choose — entering 500 g at £5.99 and entering 0.5 kg at £5.99 give the same per-kg price.
The comparison is only meaningful between products of the same type. Fresh and freeze-dried versions of the same food sell at very different densities, so comparing them by price per kg can mislead. For liquids, use a price-per-litre calculator instead.
Frequently asked questions
Enter each pack's price and weight separately, then compare the resulting "price per kg" figures. The lower price per kg is better value, assuming equal quality and form.
Select "Ounces (oz)" as the unit — the calculator converts to grams automatically and shows price per kg alongside price per oz and per lb.
Yes. Any product sold by weight — soap, pet food, fertiliser, bulk hardware — can be compared the same way, as long as both items are the same product measured by mass.
Also known as
TG we-Calculate Editorial Team. (2026). Price Per Weight Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/price-per-weight-calculator
TG we-Calculate Editorial Team. "Price Per Weight Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/price-per-weight-calculator.
TG we-Calculate Editorial Team, "Price Per Weight Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/price-per-weight-calculator
@misc{wecalculate_price_per_weight_calculator, title = {Price Per Weight Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/price-per-weight-calculator}}, year = {2026}, note = {TG we-Calculate} }
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