Pizza Party Calculator: How Many Pizzas Do I Need?
A pizza order has to cover the flavours that everyone likes and make sure that there is enough to go around. But are 2 slices of a small pizza enough, or is a single family slice more? A slice of a 16-inch family pizza holds about 1.2 regular slices and one off a 10-inch small about 0.9, so twelve family slices go further than twelve small ones. This calculator counts everything in regular slices, an eighth of a 12-inch pizza, to show how many pizzas you need for a party and how far a mixed order stretches:
- Kids' birthday party: 12 kids at 2 regular slices need 24, which is exactly 3 regular pizzas. If your twelve-year-olds eat like adults, include them in the adults and teens count instead.
- Teen sleepover: most teens eat as much as adults, if not more, so six teens at 3 regular slices need 18, which 2 large pizzas cover with 3.8 to spare. A group straight from football practice may devour 5 slices each, which takes 3 large pizzas to cover the 30 regular slices they will eat.
- Office lunch or school event: 30 adults at 3 regular slices need 9 large pizzas to cover the 90 slices. If there are chicken wings or garlic bread on the side, you may get away with 2 slices each, which means 6 large pizzas will cover the 60 regular slices for the group.
- More flavours or more pizza: four small pizzas give more variety, but at 22.2 regular slices give less total pizza compared to two family pizzas giving 28.4 slices. Fewer, bigger pizzas are often cheaper too.
Plan the pizza order
How many pizzas a party needs
Work from the guests first. Ten adults and six kids at 3 and 2 slices each eat 42 regular slices between them, which takes 8 small pizzas, 6 regular, 4 large or 3 family. The number of pizzas falls faster than you might expect. The edible pizza grows with the square of its width (as the area of a circle is pi r squared), so a 14-inch large holds about 1.4 regular pizzas and a 16-inch family about 1.8.
How the pizza is shared out
The calculator shares the pizza in the same ratio as the slices each guest eats. Ten adults and six kids who order 2 large and 2 family pizzas have 50.2 regular slices, which more than covers the 42 that they require, so each adult gets 3.6, each kid 2.4, and 8.2 are spare. Short on pizza, everyone's share shrinks in proportion: one regular pizza for 4 adults at 3 slices leaves each with 2.0. Reduce the slices per person when there is garlic bread, salad or birthday cake, and raise them when you want leftovers for the next day. If you have a combo deal on large or family sizes, enter the best deal and see if it is enough.
Frequently Asked Questions
- How many pizzas do I need for 20 people?
- Eight regular 12-inch pizzas feed 20 adults at 3 slices each, since they need 60 regular slices. Six large pizzas or five family pizzas also cover it, at 65.3 and 71.1 regular slices. A mix works too: four family pizzas and one small come to 62.4, with a couple of slices spare. If some of the 20 are kids at 2 slices each, the order shrinks, so count them separately.
- How many pizzas do I need for 10 kids?
- Three regular 12-inch pizzas cover 10 kids at 2 regular slices each, which is 20 slices with 4 to spare. Two large pizzas also cover it, at 21.8 regular slices, and so do four smalls at 22.2. Add any parents who stay to eat: each adult at 3 slices needs another 3/8 of a regular pizza, so three parents push the order to a fourth regular.
- How many slices are in a large pizza?
- A 14-inch large pizza is often cut into 10 slices, which add up to about 10.9 regular slices, a regular slice being one eighth of a 12-inch pizza. A 10-inch small is cut into 6, a 12-inch regular into 8 and a 16-inch family into 12. Slice size grows with the pizza, so for a kid, two slices off a small come to 1.9 regular slices and two off a family to 2.4.
- How many slices of pizza does an adult eat?
- Plan on 3 regular slices for each adult or teen and 2 for each kid, where a regular slice is an eighth of a 12-inch pizza. Sort guests by appetite rather than age: a hungry ten-year-old belongs with the adults and a light-eating adult with the kids. Adjust if you know your guests' appetites. The count changes with the size, so an adult's 3 regular slices are about 2.5 slices off a family pizza or 3.2 off a small.
- Is one large pizza more than two small pizzas?
- No, two 10-inch smalls are slightly more pizza than one 14-inch large: about 157 square inches against 154. In regular slices that is 11.1 against 10.9, a difference of under a quarter of a slice. The gap opens up at the top end, where two 12-inch regulars come to 226 square inches and one 16-inch family to 201, a gap of about 1.8 regular slices.
- How many pizzas should I order with other food?
- Plan on 2 slices each instead of 3 and the order shrinks: twelve adults then need 24 regular slices instead of 36, which takes 2 family pizzas rather than 3, with 4.4 slices spare. Sandwiches, salad or garlic bread on the table are the usual reason to do it. If you are making the sides yourself, scale those recipes to the same headcount. Scale a side dish for the crowd
More conversions
Convert ingredient measurements or fresh fruit and vegetables.
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