Pizza Calculator — How Many Pizzas to Order
~30 seconds
Enter your headcount, slices per person, and pizza size. The calculator totals the slices needed and divides by the slices-per-pizza for that size (US chain convention), rounding up to whole pizzas. Add a leftovers buffer if you want extra. Slice counts are conventions — adjust to your crowd.
What this calculator determines
It calculates how many whole pizzas to order by totaling the slices needed and dividing by the slices-per-pizza for the size you choose, rounding up.
Related calculators
Examples
20 people, 3 slices, 14"
20 people, 3 slices each, 14" pizza (8 slices)
Calculation
- Total slices = 20 × 3 = 60
- Pizzas = ceil(60 ÷ 8) = 8
8 pizzas
Assumptions & Conventions
- Slices per pizza is a US chain convention
- Slices-per-pizza come from a US chain convention (for example, 14 inch = 8 slices); some shops cut differently, so adjust if needed.
- Slices per person is a default you can change
- The calculator starts with a default of 3 slices per person, which you can change; it is not a universal recommendation.
- Whole-pizza rounding
- The pizza count is rounded up to whole pizzas, which may leave extra slices.