Unit Price Calculator
Enter the price and quantity of two or three items to find the lowest price per unit and the best value.
What this tool does
Unit price is the price divided by the quantity. Enter the price and quantity for each item in the same unit - say ounces - and the calculator gives the price per unit and names the cheapest. For 4.50 for 30 oz against 7.00 for 50 oz, the larger pack costs 0.14 an ounce and is the better value.
Divides price by quantity for each item and compares the results.
Names the best value and shows the percentage saving against the most expensive.
How to use it
- Type the unit you are comparing, such as oz or kg.
- Enter the price and quantity of item 1 and item 2.
- Optionally add a third item.
- Read the unit price for each and the best value.
Why use this calculator
Compares up to three sizes or brands on a single unit price and names the best value, with the saving as a percentage. Package sizes, "sale" labels and multipacks make it hard to see what is really cheaper. A single unit price makes the comparison fair.
Why we built it
We built the unit price calculator to compare up to three sizes or brands on one unit price, name the best value and show the saving as a percentage. The discount calculator handles sales, and the ml to grams converter helps compare liquids with solids.
Who this tool is for
- Shoppers comparing pack sizes
- Households trying to cut the grocery bill
- Small-business buyers
When to use it
- Comparing brands and pack sizes in a shop.
- Deciding whether a bulk buy is really cheaper.
- Comparing subscription tiers by price per item.
- Checking whether a multipack deal is worth it.
How it works
Unit price = price ÷ quantity. Comparing unit prices is valid only when every quantity is in the same unit: convert pounds to ounces, or litres to millilitres, first.
The saving shown is 1 − (best unit price ÷ highest unit price), expressed as a percentage.
Cheapest per unit is not always best: it can mean buying more than you can use or store, or lower quality.
A worked example
These are the values the calculator opens with, so you can see exactly what it does with them. Change any value on the page and the result updates; the figures below come from the same calculation.
| Input | Value |
|---|---|
| Unit | oz |
| Item 1 price | 4.5 |
| Item 1 quantity | 30 |
| Item 2 price | 7 |
| Item 2 quantity | 50 |
| Item 3 price | 0 |
| Item 3 quantity | 0 |
| Currency symbol | $ |
With those inputs, the calculator returns:
- Best value: Item 2
- Item 1: $0.1500 per oz
- Item 2: $0.1400 per oz
- Saving, best vs dearest: 6.7% less per oz
What you give it, and what you get back
| Item | Details |
|---|---|
| Unit | A label for display only; it does not convert anything. |
| Price and quantity | For each item, in the same unit. Items with a zero price or quantity are ignored. |
| Currency | An optional symbol. |
| Result | Unit price for each item, the best value and the saving. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| "Enter a price and a quantity for at least two items" | Fewer than two items were filled in. | Fill in items 1 and 2. |
| Results look wrong | The quantities are in different units. | Convert them to the same unit first. |
| Best value is more than I need | The cheapest unit comes in a larger pack. | Consider waste and storage. |
| Prices include different taxes | One price has tax and one does not. | Compare like with like. |
Assumptions and limitations
- Up to three items.
- No unit conversion: you must enter the same unit.
- Price per unit ignores quality and waste.
Frequently asked questions
How do I calculate unit price?
Divide the price by the quantity. 3.00 for 12 items is 0.25 each.
How do I compare different sizes?
Enter each one's price and quantity in the same unit and compare the price per unit.
Is the bigger pack always cheaper?
Not always. Compare unit prices - sometimes the smaller pack is on offer.
Can I compare different units?
Convert to the same unit first, such as grams or millilitres.
Can I use it for non-food items?
Yes - any items with a price and a quantity.
Is it free and private?
Yes. It runs in your browser.