The Ratio You Need When Ordering Pizza For 20 People Or More

If you are throwing a party, pizza is a great way to feed a large group while keeping everyone happy because who doesn't like pizza? However, unless you are a pizzaiolo with a backyard pizza oven, you probably aren't making all those pizzas at home. So, you'll have to get them delivered, which raises the dilemma — how many pizzas should you order? If you want to be exact, you can start by asking each guest how many slices they think they will eat. According to Giordano's, a popular Chicago-based pizza chain, the average large pizza has 10 pieces. If you take the number of slices everyone will eat, add them together and divide by 10, you should have your answer! If only it were that simple.

Most people usually don't know exactly how much pizza they will eat, and you probably don't want to spend your time asking everyone how many slices they want. It might be easier to use a pizza calculator. This pizza calculator tells you that for 20 guests, you'll need to order around eight large pizzas. But how did they get that answer?

How to calculate how much pizza you need

It looks like most pizza calculators operate on the same formula, which Hungry Howie's has dubbed the ⅜ pizza rule. It basically means you can figure out how much pizza you need for any size party by multiplying the number of attendees by ⅜. This method is, of course, based on averages and won't be exact, but it can give you a good idea of where to start. 

You can change the number based on your knowledge because you will always have more information about your guests. For example, if your party is full of big eaters, you might want to add an extra pizza or two to the order, just in case. However, other factors will determine how much pizza you need, including what kind of crust, how many toppings are on each pie, and how big the pizza actually is because not all large pizzas are created equal.

Variables that will effect the pizza ratio

What kind of crust you order can impact how many pizzas you need. If you order stuffed crust or Chicago-style deep dish, you will likely need fewer pizzas than if you were to order thin crust. The same goes for toppings; plain cheese pizzas are often less filling than four-topping veggie-covered slices. So, you will need to consider this when ordering and change the number of pizzas accordingly.

The last thing you need to consider when deciding how much pizza to order is how big the pizza will be from your restaurant of choice. Most pizzerias offer small, medium, and large-sized pies, but the exact size of each could be a little different. A large pizza from Domino's is 14 inches, and an extra large is 16 inches, whereas New York-style pies are typically 18 inches. So, if you are ordering a large from Domino's, you'll need more pizzas than if you are ordering a New York 18-inch large.

As a rule, it's a safer bet to order one more pizza than you think you'll need to ensure no one goes hungry. Once you know how many pizzas you want to order, the next step is even more controversial: figuring out the best pizza toppings!