Pizza Size Calculator
Enter the diameter, price and number of pizzas for two deals. The calculator compares the total area, works out the price per square inch and tells you which is better value.
- Area compared
- Price per square inch
- Two deals side by side
Diameters are in inches. Use any currency for price, as long as both deals use the same one.
A pizza twice as wide has four times the pizza. Area grows with the square of the diameter. A 16 inch pizza has about 201 square inches, while a 12 inch has 113. That means one large is often far better value than two mediums, even when the price looks similar.
Pizza size chart
Area and servings by diameter. Search for a size.
| Diameter (in) | Diameter (cm) | Area (sq in) | Slices | Serves |
|---|---|---|---|---|
| 8 | 20 | 50 | 4 | 1 |
| 10 | 25 | 79 | 6 | 1 to 2 |
| 12 | 30 | 113 | 8 | 2 |
| 14 | 35 | 154 | 8 | 3 |
| 16 | 40 | 201 | 8 | 4 |
| 18 | 45 | 254 | 10 | 5 |
| 20 | 50 | 314 | 12 | 6 |
| 24 | 60 | 452 | 12 | 8 to 9 |
Servings assume about 50 square inches per adult, roughly three slices of a 14 inch pizza.
Diameter and area
Compared with a 12 inch pizza. Slide the diameter.
Going from 12 to 14 inches adds 36% more pizza. Going to 16 inches adds 78%.
How to compare pizza deals
Area, not diameter. Step through it.
Halve the diameter
That is the radius.
Thick crust and wide rims eat into the topped area. For a fairer comparison, take a couple of inches off the diameter of crusty pizzas.
One large or two mediums
The classic pizza question. Compare the options.
201 square inches in one pizza.
226 square inches across two pizzas.
236 square inches, but lots of crust.
Two mediums give more variety of toppings. If value matters most, the large usually wins.
Ordering for a group
Avoid running out. Tick each item.
Tick each item as you go.
Teenagers and hungry adults can eat 70 square inches or more each. Kids under ten usually eat about half an adult portion.
What you get
Every way to compare. Each tile explains one result.
The lower price per square inch.
For each deal.
Both deals side by side.
How much more you get.
How many smalls equal one large.
Price per square inch is the fairest way to compare deals from different shops or sizes.
Frequently Asked Questions
No question matches that search.
Is a 16 inch pizza bigger than two 12 inch pizzas?
No. Two 12 inch pizzas are 226 sq in, a 16 inch is 201 sq in, so the two 12s have a little more.
How many square inches is a 14 inch pizza?
About 154 square inches.
How do I calculate pizza area?
π × (diameter ÷ 2)². For a 12 inch pizza, 3.1416 × 36 = 113 sq in.
How many people does a large pizza feed?
A 16 inch pizza feeds about four adults.
How many 10 inch pizzas equal an 18 inch?
About 3.2.
Why is a large pizza better value?
Area grows faster than diameter, while prices usually rise more slowly.
How many slices are in a large pizza?
Usually eight for a 14 to 16 inch, and 10 to 12 for 18 inches or more.
Get the most pizza for your money
Compare area, not diameter, and divide the price by the square inches. The answer is often a surprise, and it makes ordering for a crowd easy.
More size calculators
Each one has its own calculator, worked examples and answers to common questions.