Pizza Calculator – Find How Many Pizzas to Order

Have a crowd to feed and need a quick, easy, and delicious meal for the party? We’ve got you covered!

Enter the number of guests and calculate how many pizzas you should order.

Pizzas Needed:

small pizzas
medium pizzas
large pizzas
extra-large pizzas
Make your own wood-fired pizzas for your next party with an Ooni wood-fired pizza oven!
Learn how we calculated this below

scroll down

On this page:

How Many Pizzas Do You Need?

Ordering pizza for a group can be challenging. If you’re like us, then you’ve probably found yourself scratching your head trying to figure out just how many pies you should order on more than one occasion.

The amount of pizza you need for a party will vary by the number of guests, their hunger level, and the type of pizza ordered.

A good rule of thumb is to allow three slices per adult and two slices per child of a traditional crust pizza.[1]

Of course, if everyone is starving, then consider upping those numbers a bit by one or two slices.

Most large pizzas have eight to ten slices per pie, so you should probably order a large pizza for every three adults and four to five children.

And that brings us to the pizza formula.

Infographic showing how many pizzas you need for a party

The Pizza Formula

After plenty of parties, er, research sessions, we’ve discovered the perfect pizza-ordering formula.

p = 3a / 8

Thus, the number of pizzas p you should order is equal to 3 times the number of guests a, divided by 8.

And don’t just take our word for it. The fine folks over at Green Lantern Pizza, who are experts at pizza if there ever were, suggest that a ratio of 3/8 is the right ratio of pizza to order for a party.[2]

On that note, if you’re planning a party, you should check out our cake calculator to estimate how much cake you’ll need as well.

How Many Pizzas Should You Order?

The following chart shows how many pizzas to order for your party.

Table showing how many large 14″ pizzas you should order to feed a party.
Guests Pizzas Needed
5 2 pizzas
10 4 pizzas
15 6 pizzas
20 8 pizzas
25 10 pizzas
30 12 pizzas
40 15 pizzas
50 19 pizzas

Pro Tips When Ordering Pizza for a Group

Here are a few tips to consider before you order.

Order the largest size: Although the extra-large is most certainly more expensive than a medium, larger pizza sizes often cost less per slice than smaller ones, so the order will likely be cheaper overall.

Look for deals: Pizza shops often offer discounts and coupons, so it might be worth looking around for the best offer, especially for a larger order.

Pick up instead of delivery – Most pizza shops charge a premium for delivery, and it’s considerate to leave a generous tip for a large order. Delivery also often takes longer as the driver may have other stops before yours and isn’t sitting around the kitchen waiting for your order to be completed.

If you’re also in charge of hosting Thanksgiving or Easter, check out our turkey size and ham size calculators.


  1. Brittany Burke, The Right Amount of Pizza to Order for a Party,
  2. Fichter, C., How Many Pizzas Do You Need to Order?, Green Lantern Pizza,