Price Comparison Calculator
Last updated: July 2026 · Free · No sign-up required
Enter values above and click Calculate to see your result instantly.
What the Price Comparison Calculator does
Behind the inputs above sits one rule: Unit price = total price / quantity (size); compare the two unit prices. The tool evaluates it instantly with the values you enter.
If you are new to price comparison calculator, start with the worked example in the methodology section below — it walks the formula end-to-end with real numbers — then use the quick-reference table for common scenarios.
Quick reference
| Compare by | Unit to use |
|---|---|
| Groceries / food | Price per ounce, gram or 100 g |
| Drinks | Price per litre or fluid ounce |
| Paper goods | Price per sheet or 100 sheets |
| Bulk vs single | Price per item |
| Fuel / energy | Price per gallon, litre or kWh |
savings Plan with confidence
Finance decisions get a lot easier when you can see the full picture. Enter your numbers above to see total payments, interest paid, and the long-term cost of every choice — so you can compare options side by side before signing anything.
percent How the math works
We use the standard amortization, compound-interest and present-value formulas published by the Consumer Financial Protection Bureau and the Federal Reserve. The methodology block below shows every variable and rounding step we apply, so the answer is never a black box.
shield_lock Your data stays private
Every calculation happens in your browser with JavaScript — your income, balances, and loan numbers are never sent to our servers, logged, or shared. Close the tab and the inputs vanish. No sign-up, no tracking pixels on the form, no spreadsheet emailed to you later.
lightbulb Pro tip
Save the URL after you calculate — your inputs aren't stored, so write down the headline number plus the breakdown. Then come back and edit one variable at a time (down payment, rate, term) to see exactly which lever moves your monthly figure the most. That's where the real planning happens.
Interpretation guide
| Result | Meaning |
|---|---|
| Lower unit price | Better value per amount |
| Bigger pack, lower unit price | Bulk discount is real |
| Bigger pack, higher unit price | Shrinkflation — small pack wins |
| Equal unit price | Choose on freshness or storage |
Formula & methodology
Formula: Unit price = total price / quantity (size); compare the two unit prices
How the result is calculated
Comparing sticker prices is misleading when pack sizes differ. Converting each to a price-per-unit puts both products on the same basis so you can see the genuinely cheaper option.
- Pick one common unit (e.g. per ounce) and convert both pack sizes to it.
- Divide each product’s price by its quantity to get each unit price.
- The lower unit price is the better deal; multiply the difference by how much you buy to size the saving.
Example
Brand A is $4.50 for 30 oz; Brand B is $3.20 for 20 oz. A = 4.50/30 = $0.150/oz; B = 3.20/20 = $0.160/oz. Brand A wins at $0.15/oz, saving about $0.01 per ounce.