How to compare pizza size and price
Enter diameter, quantity, and price
Choose inches or centimetres, then enter the advertised diameter for each pizza. Diameter is the complete distance across the centre; it is twice the radius. Enter how many pizzas you would buy and the price of one pizza. Use the same length unit and the same currency for both options.
Calculate the total circular area
For each pizza, radius is diameter ÷ 2 and area is π × radius². The calculator multiplies one pizza’s area by its quantity. Because area depends on the square of the radius, doubling diameter makes four times the area, not twice the area.
Compare price per square unit
Each option’s total price is price each × quantity. Price per area is total price ÷ total circular area. The lower result provides more calculated area for one currency unit. The comparison also reports A’s total area divided by B’s, so 1.25× means A has 25% more circular area.
Interpret the result carefully
A mathematical tie is shown when the two price-per-area values are equal within floating-point tolerance. Editing any input removes the confirmed result and disables Copy. The calculation treats every pizza as a complete circle and does not estimate edible topping area or serving count.
Worked examples
Three 12-inch pizzas versus two 16-inch pizzas
Three 12-inch pizzas have about 339.29 in² total area. Two 16-inch pizzas have about 402.12 in². Quantities matter because the area of every pizza is included.
Equal pizzas and equal prices
If A and B each contain one 10-inch pizza priced at 10, both have about 78.54 in² and the same price per in², so the result is a tie.
Limits and validation
- Diameters and prices must be positive finite decimals. Quantities must be positive safe whole numbers. Blank, zero, negative, unit-bearing, or comma-separated entries are rejected.
- The selected length unit applies to both options. Area is displayed in the matching squared unit. Prices are treated as plain amounts in one shared currency; taxes, fees, coupons, and delivery charges are not added.
- Real pizzas may differ in crust width, thickness, toppings, shape, or usable area. A lower calculated price per area is not a claim about taste, nutrition, quality, or suitability.
Frequently asked questions
Why compare area instead of diameter?
Pizza is two-dimensional, and circular area grows with the square of radius. Diameter alone understates the difference between sizes.
Is price entered per pizza or for the whole order?
Enter the listed price for one pizza. The calculator multiplies it by quantity.
Can I compare inches with centimetres?
Both options use the one selected unit. Convert the menu measurements first if they use different units.
Does the calculator subtract the crust?
No. It compares the full ideal circular area and clearly leaves crust and topping differences outside scope.