Find out how many pizzas to order for a group, based on headcount and appetite.
How it works
Pizzas needed is the total slices required divided by slices per pizza, rounded up: pizzas = ⌈(people × slices per person) ÷ slices per pizza⌉. For 20 people at 3 slices each with 8-slice pizzas, that’s 8 pizzas.
What this does not include
The default 3 slices per person and 8 slices per pizza are widely used party-planning estimates, not exact figures — both are adjustable, since appetite varies with the crowd and slice count varies by pizza size.
How to use this calculator
- Enter the number of people.
- Adjust slices per person and slices per pizza if needed.
A worked example
20 people, 3 slices per person, 8 slices per pizza: total slices needed = 60, pizzas = 60 ÷ 8 = 8 pizzas (rounded up).
10 people at the same rate: 4 pizzas.
What the variables mean
| Variable | Meaning |
|---|---|
| People | Number of guests |
| Slices per person | Expected appetite per guest |
| Slices per pizza | How many slices each pizza is cut into |
Edge cases worth knowing
The pizza count always rounds up, never down. A partial pizza still means ordering a whole extra one, since pizzas aren’t sold by the fraction.
Zero guests makes the calculation meaningless, so the calculator declines to show a result for that input.
Why round up rather than to the nearest whole pizza?
Ordering a fraction of a pizza isn’t possible, and running short is worse than a small amount of leftovers, so rounding up is the safer default.
Should I order more for a group with mostly teenagers or big eaters?
Yes — raise the slices-per-person figure above the 3-slice default to account for bigger appetites.
Does this account for different topping preferences?
No — it only estimates total pizza count; splitting that total across different toppings or varieties is a separate decision.
