What Is a Dozen? Definition, Unit, Examples

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What Is a Dozen?

Suppose you are asked to buy a dozen bananas from a market. How many bananas will you buy? How many is a dozen? It takes 12 units to make a dozen.

A group of 12 objects or items are collectively called ‘a dozen’ items. Thus, a dozen bananas means 12 bananas. 

The word dozen comes from the French word ‘douzaine’ which means a group of 12.


Definition of Dozen

A dozen is one of the oldest units of measurement. A dozen is a grouping of twelve objects, shapes, or numbers. It is abbreviated as doz or dz. The dozen unit is used all over the world.

12 objects make a dozen

For example, a dozen eggs . . .

A dozen eggs

Or a dozen stars!

A dozen stars

Where Did the Term “Dozen” Come From?

The word dozen comes from the French word “douzaine,” which means a group of 12. Dozen is one of the most primitive customary units of numbers.

The number system with the base number 12 is called duodecimal or dozenal. It is believed to have started counting finger bones using the thumb. It is connected to nature. A day has two cycles of 12 hours, and a year has twelve months or twelve moon cycles or zodiac signs. 

A group of 12: examples

Moreover, among numbers under 18, the number 12 has the most divisors—1, 2, 3, 4, 6, and 12—allowing most subdivisions of the unit. Various things come in a dozen. Many household goods are sold in dozens.

What Is a Dozen of Dozens?

“A dozen of dozens!” It’s fun to say, isn’t it? So, what is a dozen of dozens? It is 12 dozen. Twelve dozen are called a “gross.” It is a shortening of the Old French term, grosse douzaine, which means a large dozen. 

Ten dozens are called a “small gross,” and twelve grosses are called a “big gross.” Merchants usually buy their goods in bulk and sell them in dozens.

Certain items packaged by the count of dozen are also categorized into larger sets. This practice is common when suppliers sell these items in bulk quantities.

Decimal System versus Dozen System

You may be wondering why you have to learn a new system of dozens when you can already count using the decimal system. Well, this is because a dozen calculation methods have advantages. First of all, it makes counting a few particular items easier. We are used to counting in tens, so counting in 12 can be an interesting challenge.

And 12 or a dozen is not new to us. We use it in our daily calculations, like the clock’s face has 12 digits. There are 12 hours in a day, 12 months in a year. See, we count things in 12 all the time. So, you wanted 8 eggs for a recipe, and they gave you a dozen in a packet. You know mom can always whip up some yummy scrambled eggs for breakfast the next morning. Isn’t that a lovely side benefit of the dozen?

The Sexagesimal System

“Sexagesimal system” sounds a little scary. But it is quite simple and fascinating. It is an ancient system of counting, which uses the powers of 60, pretty much the same way the decimal system uses powers of 10. This system divides the hour into 60 minutes and then the minute into 60 seconds.

Fun Facts about a Dozen 

  • A baker’s dozen is 13, one more than a proper dozen. It is also known as a long dozen. Bakers started this custom to avoid a fine for serving less than the required weight for 12 items. 
  • The number 12 was most likely used as a unit of measurement for the first time by ancient Mesopotamians.


A dozen is a widely used term when you are buying things. It is a common unit that has been in use for ages. It makes the process of counting multiple objects much easier. You also sound really smart saying it. Now that you have learned all about it, buy dozens of your favorite things the next time you go shopping, and have a gross amount of fun doing it.

A dozen roses would smell so divine

A dozen cuddles, now that would be fine

A dozen candies to eat till you are done

A dozen puppies, oh what fun,

But first, what is a dozen?

The Dynamic Dozen: An Introduction

Solved Examples on Dozen

1. Find out the values of

a) $\frac{3}{4}$ of a dozen and b) $\frac{1}{2}$ of a dozen


Fraction of a dozen: examples

a) $\frac{3}{4}$ of a dozen

A dozen is equal to 12 units. $\frac{3}{4}$ of a dozen is $\frac{3}{4} \times 12 = 9$

So, $\frac{3}{4}$ of a dozen is 9

b) $\frac{1}{4}$ of a dozen

A dozen is equal to 12 units. $\frac{1}{4}$ of a dozen is $\frac{1}{4} \times 12 = 3$

So, $\frac{1}{4}$ of a dozen is 3

2. Sam purchased 5 dozen disposable cups for a party. What is the number count of the disposable cups bought by him?


Sam purchased 5 dozen disposable cups for a party. (Given)

A dozen is equal to 12 units.

To find the number of disposable cups, multiply 5 by 12

5 dozen $= 5 \times 12 = 60$

So, Sam bought 60 disposable cups for the party.

3. Mary ordered 72 candles at Christmas time. The candles came in packets of dozens. How many packets of candles arrived?


Each packet has a dozen candles, and the total number is 72.

To find the number of dozens in 72, divide 72 by 12.

$72 \div 12 = 6$

Therefore, there were 6 packets of candles.

4. Susie sold a “small gross” of Girl Scout cookies. How many cookies did she sell?


Ten dozen are called a “small gross.”

So, Susie sold 10 dozen cookies. A dozen here refers to 12 cookies.

10 dozen will have $10 \times 12 = 120$ cookies.

Therefore, 120 cookies were sold by Susie.

5. How many dozens make up the number 240?


To find the number of dozens in 240, divide 240 by 12.

$240 \div 12 = 20$

Therefore, 20 dozens make up the number 240.

Practice Problems on Dozen

What Is a Dozen? Definition, Unit, Examples

Attend this quiz & Test your knowledge.


Which of the images given below denote a dozen donuts?

What Is a Dozen? Definition, Unit, Examples
Correct answer is: C
We know that a dozen is equal to 12 units.
Option c depicts 12 donuts, which make up a dozen.

How many dozens of colored pencils do you see in the image given below?

What Is a Dozen? Definition, Unit, Examples
1 dozen
2 dozens
3 dozens
None of the above
Correct answer is: 2 dozens
We know that a dozen is equal to 12 units.
The above picture shows 24 colored pencils.
$24 = 2 \times 12$ (a dozen)
So, we can see 2 dozen colored pencils in the image.

Maggie bought 4 dozen apples. How much is 4 dozen apples?

12 apples
24 apples
36 apples
48 apples
Correct answer is: 48 apples
A dozen apples refers to 12 apples.
4 dozen will have $4 \times 12 = 48$ apples.

What are 12 dozens called?

a small gross
a medium gross
a big gross
Correct answer is: gross
Twelve dozen are called a “gross.”

Dan has to arrange 288 strawberries in boxes. How many boxes would he need if each box can hold a dozen?

10 boxes
24 boxes
30 boxes
32 boxes
Correct answer is: 24 boxes
Each box can hold a dozen strawberries, that is, 12 strawberries.
To find the number of boxes, divide 288 by 12.
$288 \div 12 = 24$
Therefore, Dan would need 24 boxes.

Frequently Asked Questions on Dozen

As the name suggests, “half a dozen” is exactly half of a dozen. We have already learned that a dozen is equal to 12 units. So, half a dozen is equal to half of 12, that is 6 units.

Therefore, $\frac{1}{2} doz $= 6$ units

A few typical items are grouped or sold in sets of 12 or as dozens. These include eggs, flowers, cookies, and doughnuts. This is because the number 12 is easily divisible into halves, thirds, and quarters. Many manufacturers also package commonly used items, such as pencils, disposable cups, etc., by the dozen.

An amount equal to twelve dozen, 144, is called a “gross.” 12 grosses are known as a great gross; it refers to 12 times a gross. It is 12 multiplied by 144. So, a great gross is equal to 1728 items or units. It is also known as a “big gross.”

A great hundred is a cardinal number that is the product of ten and twelve. So, a great hundred is equal to 10 dozen. So, we multiply 12 by 10 to get the value 120. It is also referred to as a “small gross.”

The idiom “a dime a dozen” refers to something common and not special. If things are said to be a dime a dozen, there are many of them, and because of that, they are not particularly valuable or very interesting.