Pizza Calculator

About this calculator

This calculator works out how many pizzas to order using pizzas needed = ceil(guest count × slices per person ÷ slices per pizza), rounding up since a fraction of a pizza still means ordering a whole extra pie. Slices per person typically runs 2–3 for a meal with sides or other food present, and higher for pizza as the only food, while slices per pizza depends on size and cut style (a standard large is usually cut into 8).

Party and event planners use this to avoid the two classic pizza-ordering mistakes — running short with hungry guests left waiting, or over-ordering and wasting food and budget — and restaurants and pizzerias taking large catering orders use the same math to quote a customer the right pie count for their headcount.