Enter a product price and quantity on the left, then click Calculate to see the cost per unit.
A unit price is the cost for one single unit of a product — one ounce, one gram, one liter, or one piece. It is the most reliable way to compare products that come in different sizes or packages. You may also see it called Price Per Unit on grocery shelf labels.
For example, a 16 oz bottle for $2.40 works out to $0.15 per oz. A 32 oz bottle for $4.00 is only $0.125 per oz. The bigger bottle costs more total but gives you more product for every dollar — a better value.
Most grocery stores are required to display unit prices on shelf labels in many countries. This tool lets you calculate it yourself, compare multiple products, and always find the smarter buy.
The unit price formula is very simple:
Example: Product A costs $3.49 for 12 oz → $0.291/oz. Product B costs $5.29 for 20 oz → $0.265/oz. Product B is cheaper per ounce even though it costs more at the register. This is why knowing the cost per unit always gives you a clearer picture than the sticker price alone.
| Product Type | Best Unit to Compare | Example |
|---|---|---|
| Beverages (juice, soda, water) | Per fl oz or per ml | Cost per 100 ml |
| Cleaning products (liquid) | Per fl oz or per load | Cost per wash load |
| Paper products | Per sheet or per roll | Cost per sheet |
| Dry food (cereal, pasta, rice) | Per oz or per gram | Cost per 100g |
| Supplements / medicine | Per tablet or per mg | Cost per tablet |
| Meat / seafood | Per lb or per kg | Cost per pound |
| Nuts, coffee, snacks | Per oz or per gram | Cost per oz |
| Electricity / fuel | Per kWh or per gallon | Cost per kWh |
Shows cost per ounce (fl oz) at various package sizes and price points. Highlighted cells are the best value per row.
| Package Size | $1.00 | $2.00 | $3.00 | $4.00 | $5.00 | $6.00 | $8.00 |
|---|
Formula: Total Price ÷ Size = Cost per oz. Lower is better. Currency shown as $.
Common grocery comparison format — cost per 100 grams. Useful for cereal, nuts, pasta, snacks, and packaged foods.
| Net Weight | $1.00 | $2.00 | $3.00 | $4.00 | $5.00 | $6.00 | $8.00 |
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Formula: (Price ÷ Weight in g) × 100 = Cost per 100g. The global standard used on EU, AU, and many Asian supermarket shelf labels.
Starting from a base unit price, this table shows what you actually pay per unit after applying different discount percentages.
| Base Unit Price | 5% Off | 10% Off | 15% Off | 20% Off | 25% Off | 30% Off | 50% Off |
|---|
Discounted unit price = Base unit price × (1 − discount%). A 20% discount does not always beat a competitor's regular price — compare discounted unit prices directly.
Use this table to manually convert between units before comparing products measured in different systems.
| From | To | Multiply By | Example |
|---|---|---|---|
| 1 oz (weight) | grams | 28.3495 | 4 oz = 113.4g |
| 1 lb | grams | 453.592 | 2 lb = 907.2g |
| 1 kg | oz (weight) | 35.274 | 500g = 17.64 oz |
| 1 fl oz (US) | ml | 29.5735 | 8 fl oz = 236.6 ml |
| 1 liter | fl oz (US) | 33.814 | 0.5 L = 16.9 fl oz |
| 1 cup (US) | ml | 236.588 | 2 cups = 473.2 ml |
| 1 gallon (US) | liters | 3.78541 | 2 gal = 7.57 L |
| 1 quart (US) | ml | 946.353 | 1 qt = 946 ml |
| 1 pint (US) | ml | 473.176 | 1 pt = 473 ml |
| 1 lb | oz (weight) | 16 | 2.5 lb = 40 oz |
| 1 kg | lb | 2.20462 | 1 kg = 2.20 lb |
| 1 stone | lb | 14 | Used in UK packaging |
Tip: When comparing US and European products, convert oz to grams or fl oz to ml first, then apply the unit price formula to both.
A reference guide to how different countries regulate unit pricing in retail stores.
| Country / Region | Unit Pricing Required? | Standard Unit Used | Applies To | Governing Law |
|---|---|---|---|---|
| 🇺🇸 USA (Federal) | No federal law | Per oz / lb / fl oz | Varies by state | State laws (e.g. MA, CT) |
| 🇪🇺 European Union | Yes — mandatory | Per 100g or per 100ml | All pre-packed food | EU Price Indication Directive |
| 🇬🇧 UK | Yes — mandatory | Per 100g or per 100ml | Most food & drink | Prices Act / BIS Guidelines |
| 🇦🇺 Australia | Yes — mandatory | Per 100g or per 100ml | Food sold in stores | Trade Practices Act |
| 🇨🇦 Canada | Recommended | Per 100g or per unit | Not federally required | Competition Bureau guidance |
| 🇫🇷 France | Yes — mandatory | Per kg or per liter | Food and household products | Consumer Code Art. L113-3 |
| 🇩🇪 Germany | Yes — mandatory | Per 100g or per liter | All pre-packaged goods | PAngV (Price Indication Ordinance) |
| 🇯🇵 Japan | Encouraged | Per 100g or per unit | Voluntary in most retail | Consumer Contract Act |
| 🇮🇳 India | Yes — for packaged goods | Per unit / per kg / per liter | All packaged commodities | Legal Metrology Act 2009 |
| 🇧🇷 Brazil | Yes — mandatory | Per unit of measurement | Pre-packed consumer goods | SENACON / CDC |
Rules change — verify with local consumer protection authority. This table is for general reference only and may not reflect the most recent regulations.
How much you spend per year based on unit price and weekly consumption. Useful for household staples you buy regularly.
| Unit Price | 10 units/wk | 20 units/wk | 30 units/wk | 50 units/wk | 100 units/wk | 200 units/wk |
|---|
Annual spend = Unit price × Units per week × 52. Reducing your unit price by even $0.01 per oz adds up to real savings at scale.