How Big Is 18 Inch Pizza? (Slices, Servings, Size, And Total Calories)

How big is 18 inch pizza?


Unless you can multiply π x radius² in your head, listing out a pizza by its diameter isn’t that helpful.


Don’t worry, I’ve got you covered.

Below you’ll find answers to:

  • Is 18 inch pizza big enough to feed your guests?
  • How many slices in a 18 inch pizza? How many slices can each person have?
  • How many people does a 18 inch pizza feed?
  • What size is a 18 inch pizza?
  • How big is an 18 inch pizza?

It’s all right here.

My goal is simple: Make sure you always order enough pizza.



Because there’s nothing worse than running out of pizza.

Beyond that, you can check out my the table below for a quick reference on how a 18 inch pizza compares to other popular sizes so you know exactly how much pizza to order.


How Big Is 18 Inch Pizza?

An 18 inch pizza is usually considered an jumbo pizza, has 12 slices, and serves 4-6 adults.

An 18 Inch Pizza Feeds How Many?

18 inch pizza feeds 4-6 adults, depending on how hungry each of you are.


An 18 inch pizza has 12 slices, enough for each person to have 2-3 slices each.

How Many Slices In 18 Inch Pizza?

A 18 inch pizza will come in 12 slices.

How Many Calories In 18 Inch Pizza?

The calories in a slice of pizza varies dramatically depending on the toppings and exact size of each slice.



The total number of calories in an 18 inch pizza is roughly 3,563, assuming you get a pepperoni pizza. This comes out to 297 calories per slice.

What Size Is 18 Inch Pizza?

An 18 inch pizza is usually considered to be a jumbo pizza.

You can use my chart below to compare it to other common sizes.

How Big Is an 18 Inch Pizza (Total Area)?

With a diameter of 18 inches, the total size of an 18 inch pizza is 254 square inches, which comes out to about 21 square inches per slice.

You can calculate the total area of any pizza by multiplying π x radius².

If you don’t feel like doing math, just use my chart below to compare 18 inch pizza to the other most popular pizza sizes.

18 Inch Pizza Size Comparison

If you’re trying to decide whether or not an 18 inch pizza is big enough, here’s a chart you can use:

SizeInchesServingsSlicesTotal SizeTotal Calories
Small/Personal10 inch1-2 adults4 slices79 square inches1,100 calories
Medium12 inch2-3 adults6 slices113 square inches1,583 calories
Large14 inch3-4 adults8 slices154 square inches2,155 calories
Extra Large16 inch3-5 adults10 slices201 square inches2,815 calories
Jumbo18 inch4-6 adults12 slices254 square inches3,563 calories

Although the difference in diameter is only 2 inches, an 18 inch pizza is 25% bigger than a 16 inch pizza.

Remember, even though the diameter of each size is only slightly different, the total amount of pizza you’re getting from each additional size up is very different.

18 Inch Pizza Size Comparisons

Now that we know how big is 18 inch pizza, let’s take a closer look at how it compares to other popular pizza sizes.

10 Inch Pizza vs 18 Inch Pizza: A 10 inch pizza is less than 1/3 of the size of an 18 inch pizza. It has just 4 slices compared to the 12 slices in an 18 inch pizza.

12 Inch Pizza vs 18 Inch Pizza: A 12 inch pizza is a medium pizza and serves 2-3 adults, whereas an 18 inch pizza is a jumbo that serves 4-6 adults. A 12 inch pizza is about 55% smaller than an 18 inch pizza.

14 Inch Pizza vs 18 Inch Pizza: A 14 inch pizza is a large pizza and serves 3-4 adults, whereas an 18 inch pizza serves 4-6 adults. An 18 inch pizza has 50% more slices than a 14 inch pizza.

16 Inch Pizza vs 18 Inch Pizza: A 16 inch pizza serves 3-4 adults and is about 3/4 the size of an 18 inch pizza.

Read more

Why Pizza Size is Important

Pizza size is important for 2 reasons: serving size and price.

1. Serving Size

You always want to make sure you have enough pizza. There’s nothing worse than running out of pizza, especially when you were the one in charge of ordering it. Use the chart above to determine how much pizza and in what sizes you should order for your group.

For example, if I was serving 10 adults, I would order two 18 inch pizzas.

Check out my full guide to pizza sizes.

2. Price

You can get more pizza for a better price by ordering a larger size. 2 medium pizzas will be much more expensive than 1 large, and you’ll only be getting slightly less pizza.

If you’re trying to decide between 2 sizes, I always recommend ordering the bigger size – who doesn’t love leftover pizza?

And remember, just a pizza that is just 2 inches bigger in diameter will have much more pizza.

Now that we’ve explored the 16 inch pizza size, let’s look at some tips for choosing the right size for your next pizza night.

18 Inch Pizza Size Tips: How To Choose The Perfect Pizza Size For Your Occasion

Now that we’ve answered how big is 18 inch pizza, here’s how to pick the perfect pizza size for your next gathering by keeping these things in mind:

1. Think about how many people you’re feeding and how much they’ll each be eating. If you’re ordering pizza for yourself or for you and 1 other person, a 10 inch pizza might be perfect. If one of you is extra hungry, I would recommend ordering a 12 inch pizza.

2. Consider your budget when choosing a pizza size. 16 inch pizzas are usually more expensive than 12 inch pizzas, so if you’re on a tight budget, you may want to stick with the smaller size. That said, if you’re ordering multiple pizzas, it’s cheaper to order a larger size.

3. Think about the type of occasion you’re having. If it’s a casual get-together, a 12 inch pizza may be fine, especially if you don’t mind running out of food. But if you’re hosting a formal event or feeding a large group of people, a 16 inch pizza will give you the most bang for your buck and ensure everyone goes home with a full belly.

18 Inch Pizza Recipes

Final Word: 18 Inch Pizza

Nothing beats the feeling of hosting a big group of your friends and eating really good pizza.

18 inch pizzas are the best value pizzas you can order – the bigger the size, the lower the cost per square inch of pizza.

I know what I’m ordering for dinner tonight!


FAQs - 18 Inch Pizza

How many slices is an 18-inch pizza?

There are 12 slices in an 18-inch pizza.

How big is an 18-inch pizza?

An 18-inch pizza is usually considered a jumbo pizza, has 12 slices, feeds 4-6 adults, and is 254 square inches.

How many does an 18-inch pizza feed?

An 18-inch pizza will feed 4-6 adults. It will come in 12 slices, enough for each person to have 2-3 slices.

How much bigger is an 18-inch pizza than a 14 inch?

An 18-inch pizza is more than 1.5x bigger than a 14 inch pizza, in terms of total area. An 18 inch pizza will come in 12 slices and can feed 4-6 adults, whereas a 14 inch pizza will come in 8 slices and feed 3-4 adults.