How many pizzas do you need?
A common rule of thumb is 3 slices per adult and 2 per child for a casual meal. Hungrier crowds or pizza-only parties run closer to 4 slices each. This pizza calculator multiplies your headcount by slices per person, then divides by the slices in your chosen pizza size and rounds up.
Slices by pizza size
- Small (10") — about 6 slices
- Medium (12") — about 8 slices
- Large (14") — about 10 slices
- Extra-large (16–18") — about 12 slices
Ordering tips
Order a little extra if you have teenagers, a long event, or few other foods. Offer at least one vegetarian option, and remember leftover pizza keeps well.
Frequently asked questions
How many pizzas do I need for a party?
Enter your guest count and appetite into this pizza calculator. As a rule of thumb, plan 3 slices per adult — so a large 10-slice pizza feeds about 3 people. For 10 people that's roughly 3–4 large pizzas.
How many slices are in a large pizza?
A large (14-inch) pizza is usually cut into 10 slices, a medium into 8, and a small into 6. Extra-large pies can have 12. The tool lets you pick the size you're ordering.
How many pizzas for 20 people?
At 3 slices each, 20 people need about 60 slices — roughly 6 large pizzas. Bump it to 7 if your crowd is hungry or pizza is the only food being served.