What is Pizza Party Calculator?
Pizza Party Calculator is a free online tool that tells you how many pizzas to order for a party. You enter the number of guests, how hungry they are and the pizza size you want. The calculator then shows how many pizzas you need and how many slices you will get.
It works for any kind of group: birthday parties, office lunches, school events, sports teams, game nights and family get-togethers.
Why we built it
Ordering pizza for a group sounds easy, but most people end up guessing. Order too little and guests go hungry. Order too much and you pay for boxes of pizza nobody eats. We built this site to take the guesswork out of it, so you can place your order in a minute and get back to planning the party.
How the calculator works
The math is simple and we want you to see it:
- Slices needed = (adults x adult slices) + (teens x teen slices) + (kids x kid slices)
- Pizzas needed = slices needed ÷ slices per pizza, rounded up to the next whole pizza
These are the numbers the calculator uses:
| Setting | Value used |
|---|---|
| Slight appetite | Adults 1, teens 2, kids 1 slice each |
| Normal appetite | Adults 2, teens 3, kids 1 slice each |
| Very hungry | Adults 3, teens 4, kids 2 slices each |
| Small pizza | 8 slices |
| Medium pizza | 10 slices |
| Large pizza | 8 slices (or 12 with a party cut) |
| X-Large pizza | 16 slices |
For example, 10 adults with a normal appetite need 20 slices. With large pizzas of 8 slices each, that is 20 ÷ 8 = 2.5, which rounds up to 3 large pizzas.
The calculator also shows a less waste option. It fills your order with your chosen size, then covers the last few slices with one smaller pizza instead of a whole extra large one. If you add a price per pizza, it also shows the total cost and the cost per person.
Pizza shops do not all cut their pizzas the same way. Most US chains cut a large pizza into 8 slices, but some shops use a 12 slice party cut. The calculator lets you pick 8 or 12 slices so the result matches your shop.
What we are not
- We do not sell pizza and we do not take orders.
- We are not linked to any pizza chain or restaurant.
- We do not ask you to sign up. The calculator is free and runs in your browser.
Get in touch
Found a mistake, or have an idea that would make the calculator better? We would love to hear from you. Send us a message on our Contact page.