Unit Price Calculator
Compare products of different sizes by price per unit, per 100 g or per litre to see which is cheaper
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Converts products of different sizes to the same basis, such as price per 100 g, per litre, per ounce or per item, and shows which one is cheaper. Pack counts, free-item deals, coupons and shipping are included in what you actually pay.
How to use
- For each product enter "Price", "Size or amount", "Unit" and "Pack count". A size such as 500×6 also works.
- Press "Add product" to compare more products (up to 8).
- Open "Deals and shipping" to enter a "Free item deal", a "Coupon" or "Shipping".
- Read the cheapest product and its unit price at the top, and change the basis under "Show price per".
- Check "What price would make it cheaper" for the price each product would need, and press "Copy result" to copy the ranking.
How it works
- Unit price = amount paid ÷ total quantity. Amount paid = price × packs paid for, minus the coupon, plus shipping; total quantity = size × pack count × packs received (buy 1 get 1 free gives two packs for one price).
- Weight (g, kg, oz, lb), volume (mL, L, fl oz, cup, gal), count (items, pieces, rolls, sheets) and length (m, ft) are only converted within the same kind. Mixed kinds are ranked separately and a warning is shown.
- oz is the avoirdupois ounce; fl oz, cup and gallon are US units, converted with NIST factors. No exchange rates are applied.
- The products you enter are saved only in this browser.
Questions and answers
- How do I calculate price per ounce?
- Divide the price by the number of ounces. A 24 oz jar at $4.80 costs 4.80 ÷ 24 = $0.20 per ounce.
- Is the bigger package always cheaper?
- No. Larger sizes are often cheaper per unit, but sales and coupons on smaller sizes can reverse that. Enter both to see the unit prices side by side.
- How does shipping change the result?
- Shipping is added to the amount paid, so the unit price rises. The smaller the order, the more shipping weighs.
- Can I compare a product sold by weight with one sold by volume?
- No. Weight and volume cannot be converted without the density of each product, so such products are ranked separately.