Plan about 3 slices of a large pizza per adult (2 for light eaters, 4 for big appetites and teenagers) and 2 for children. Order a mix of plain cheese, pepperoni and a vegetarian option, and remember leftovers are rarely a problem.
How to use the Pizza Party Calculator – How Many Pizzas to Order
- Adults
- Children
- Appetite
- Pizza size
- Pizza type
- Price per pizza
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the number of adults and children, their appetite, the pizza size and type, and the price per pizza.
Tips
- Order by area, not by diameter: a 16″ pizza has almost twice the area of a 12″ one.
- Plan about 3 slices per adult for a meal, more for big appetites and teenagers.
- For homemade pizza, cold-ferment the dough for 24–72 hours for better flavour.
- Preheat the oven and the stone or steel for at least 45 minutes.
Common mistakes to avoid
- Comparing prices per pizza instead of per square inch.
- Forgetting that a thick crust eats into the topping area of a small pizza.
- Over-topping homemade pizza, which leaves the middle soggy.
Inputs explained
| Field | What to enter |
|---|---|
| Adults | A number |
| Children | A number |
| Appetite | Choose one: Light – 2 slices each, Average – 3 slices each, Hungry – 4 slices each, Teen athletes – 5 slices each |
| Pizza size | Choose one: Small (10 in / 25 cm), Medium (12 in / 30 cm), Large (14 in / 36 cm), Extra large (16 in / 40 cm) … |
| Pizza type | Choose one: Cheese, Veggie, Pepperoni, Meat lovers / bacon and cheese … |
| Price per pizza | Amount in your currency |
What each result means
- Slices needed = [Adults]×[Appetite] + [Children]×2
- Pizzas to order = ceil([Slices needed]÷[Slices per pizza])
- Leftover slices = [Pizzas to order]×[Slices per pizza] – [Slices needed]
- Total cost = [Pizzas to order]×[Price per pizza]
- Cost per person = [Total cost]÷([Adults] + [Children])
Example values
How the main result changes when Adults changes and everything else stays at the example values above:
| Adults | Pizzas to order |
|---|---|
| 5 | 3 |
| 7.5 | 4 |
| 10 | 4 |
| 12.5 | 5 |
| 15 | 6 |
| 20 | 7 |
Formula
Slices needed = adults × slices per adult + children × 2
Pizzas = ⌈slices ÷ slices per pizza⌉
Calories per slice ≈ calories per in² × pizza area ÷ slices
Worked example
Inputs — Adults: 10; Children: 4; Appetite: Average – 3 slices each; Pizza size: Large (14 in / 36 cm); Pizza type: Cheese; Price per pizza: $16.
Results — Slices per pizza = 10; Slices needed = 38; Pizzas to order = 4; Leftover slices = 2; Total cost = $64.00; Cost per person = $4.57; Calories per adult (approx.) = 647 kcal.
Frequently asked questions
How many pizzas for 20 people?
About 6–8 large pizzas (10 slices each) at 3 slices per adult.
How many slices are in a large pizza?
Usually 8–10 for a 14 in pizza.
How many pizzas do kids eat?
About 2 slices of a large pizza per child.