About the Pizza Size Comparison Calculator
The diameter of a pizza tells you less than you might think, because the amount of pizza depends on the area, which grows with the square of the diameter. A 16 inch pizza has far more than 4 inches' worth more than a 12 inch one. This calculator takes the diameter and the price of two pizzas and shows the area of each, the price per 100 square inches (or square centimetres), which one is the better value and how much bigger the larger pizza is. Type the diameter and price of two pizzas and the pizza value appears at once, with a few related figures underneath, and you can copy the result with one tap. The sums run in your browser, so nothing you enter is uploaded.
Updated October 2026
How to use the Pizza Size Comparison Calculator
- 1Enter the diameter and price of two pizzas.
- 2Pick the units or options from the menus if the pizza value tool offers them.
- 3Read the pizza value in the large result box.
- 4Look at the extra rows for related figures.
- 5Press Copy result to keep the answer.
When you need the pizza value
The comparison works for anything round and priced by size: pizzas, cakes, pies, pancakes or even round rugs. Families use it to decide between sizes, and shops use it to set fair prices for sizes.
Doubling the diameter gives four times the area. This is why large pizzas are nearly always better value, unless the price jumps a lot. Very thick or stuffed crust changes the amount of food, which area alone does not capture.
How the pizza value is worked out
Area = π × (diameter ÷ 2)². Price per area = price ÷ area. Larger by = area of the bigger ÷ area of the smaller − 1. A 12 inch pizza at 10 has an area of 113.1 square inches, or 8.84 per 100 square inches. A 16 inch pizza at 15 has 201.1 square inches, or 7.46 per 100. The larger pizza has 77.8 percent more pizza, and costs 50 percent more, so it is the better value.
Every answer on this page comes from that one rule, so you can check any result by hand with a calculator. The figures shown underneath, such as other units, are conversions of the same answer.
- Area, price per area, winner
- Inches or centimetres
- How much bigger
Mistakes to avoid with pizza value
Make sure that the diameters use the same unit for both pizzas. The tool compares area, not toppings, thickness or crust. Check also that the quoted size is the diameter and not the length of a square tray.
On phone and computer
On a phone, type into the boxes one after another and read the pizza value underneath; Copy result puts it on the clipboard for a message or a note. On a computer the inputs sit on the left and the answer on the right, so you can change one figure and watch the pizza value move. The pizza size comparison calculator works the same on both. Bigger pizzas can be much better value than they look. Use the Unit Price Calculator for price per unit, the Circle Calculator to check the area of a round pizza, and the Discount Calculator to include a coupon.
Features
- Area grows with the square
- Same unit for both
- Crust thickness not included
- Clear messages when the pizza value inputs make no sense
- Copy the result with one tap
- Private: nothing is uploaded
Frequently asked questions
How do I calculate pizza value?
Area = π × (diameter ÷ 2)². Price per area = price ÷ area. Larger by = area of the bigger ÷ area of the smaller − 1. A 12 inch pizza at 10 has an area of 113.1 square inches, or 8.84 per 100 square inches. A 16 inch pizza at 15 has 201.1 square inches, or 7.46 per 100. The larger pizza has 77.8 percent more pizza, and costs 50 percent more, so it is the better value.
What is the formula for pizza value?
Area = π × (diameter ÷ 2)². Price per area = price ÷ area. Larger by = area of the bigger ÷ area of the smaller − 1. The pizza size comparison calculator applies it exactly and rounds only the displayed answer to six significant figures.
Is a bigger pizza always better value?
Often, because area grows with the square of the diameter, but it depends on the prices.
How much more pizza is a 14 inch than a 12 inch?
About 36 percent more area.
What about square pizzas?
Use area = side × side. This tool is for round ones.
Is this pizza size comparison calculator free and private?
Yes. It is free, needs no account and runs in your browser, so the numbers you type are not uploaded or stored.