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Pizza Calculator

Stop guessing and start eating. Enter how many people are showing up, pick your pizza size, and this calculator tells you exactly how many pies to order so nobody goes hungry and you don't end up with a fridge full of cold slices.

The math behind pizza ordering is surprisingly simple once you know the numbers:

  • Adults eat about 3 slices on average
  • Children eat about 2 slices on average
  • Most pizzas are cut into 8 slices regardless of size

So for 10 adults, that's 30 slices, which means you need 4 large pizzas (32 slices total). Easy.

Pizza Size Comparison

SizeDiameterAreaSlices
Small10"78 in²8
Medium12"113 in²8
Large14"154 in²8
Extra Large16"201 in²8

Pro tip: Two large pizzas (308 in²) give you way more pizza than one extra large (201 in²) for roughly the same price. The area increases with the square of the radius, so bigger sizes are almost always a better deal per square inch.

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