Pizza quantity estimator
Work out how many pizzas to order for a party, from your guest count and expected slices per person.
Result
Pizzas needed
How to use this calculator
- Enter the number of guests.
- Set slices per guest and slices per pizza.
- Read the number of pizzas to order.
Assumptions
- Assumes all guests eat a similar amount of pizza — adjust the slices-per-guest figure if pizza isn't the only food on offer.
Technical details: what the fields mean
- Number of guests
guests - Total number of guests expected.
- Slices per guest
slicesPerGuest - Expected slices per person — 3 is typical if pizza is the main food, less if there are other dishes too.
- Slices per pizza
slicesPerPizza - How many slices one pizza is cut into — 8 is standard for a large pizza.
Methodology
Pizzas needed = ceil(guests × slices per guest ÷ slices per pizza).
Worked example
20 guests, 3 slices each, 8-slice pizzas
Inputs: guests=20, slicesPerGuest=3, slicesPerPizza=8
Result: 8 pizzas
Practical guidance
- If pizza is one of several dishes rather than the main food, reduce slices-per-guest to 1–2.
Common mistakes
- Rounding down the pizza count instead of up, leaving some guests short.
FAQs
How many pizzas do I need for 20 people?
At 3 slices each with 8-slice pizzas, 8 pizzas.