Have you ever wondered how many zeros are in a million? One billion? a trillion? Do you know how many zeros are in a vigintillion? Someday you might need to know this for a science or math class. Then again, you might want to impress a friend or teacher.
How Many Zeros in a Trillion? How Large Numbers Are Made
The digit zero (0) is important for counting large numbers. The larger the number, the more zeros it has.
Starting with 1,000, there are a large number of groups of 0’s. Each time you jump to the next level of the number, another 0 is added.
There are three 0s (1,000) in the number one thousand. There are four 0s in the number 10,000 (10,000). There are five 0s in the number one lakh (100,000). The number one million has six 0’s (1,000,000).
Every time you have a whole set of three zeros, such as in a million (1,000,000), you use a comma to separate them.
One Trillion

Number of Zeros 12

1,000,000,000,000

Numbers Bigger Than a Trillion
The zero digit plays an important role when you count very large numbers. It helps to track these multiples of 10 because the larger the number, the more zeros are needed. In the table below, the first column lists the name of the number, the second provides the number of zeros that follow the initial digit, and the third tells you how many groups of three zeros you need to write each number.
Name  Number of Zeros  Groups of (3) Zeros 

Ten  1  (10) 
Hundred  2  (100) 
Thousand  3  1 (1,000) 
Ten thousand  4  (10,000) 
Hundred thousand (One Lakh)  5  (100,000) 
Million (Ten Lakh)  6  2 (1,000,000) 
Billion  9  3 (1,000,000,000) 
Trillion  12  4 (1,000,000,000,000) 
Quadrillion  15  5 
Quintillion  18  6 
Sextillion  21  7 
Septillion  24  8 
Octillion  27  9 
Nonillion  30  10 
Decillion  33  11 
Undecillion  36  12 
Duodecillion  39  13 
Tredecillion  42  14 
Quatttuordecillion  45  15 
Quindecillion  48  16 
Sexdecillion  51  17 
Septendecillion  54  18 
Octodecillion  57  19 
Novemdecillion  60  20 
Vigintillion  63  21 
Centillion  303  101 
All of Those Zeroes
A table like the one above can certainly be helpful listing the names of all numbers, depending on how many zeros they have. But it can be really mindboggling to see what some of those numbers look like. Below is a list—including all zeros—for numbers up to a decimal—a little over half of the numbers listed in the table above.
Name

Number of Zeros

Written Out

One Thousand

3

1,000

Ten Thousand

4

10,000

One Hundred Thousand

5

100,000

One Million

6

1,000,000

Billion

9

1,000,000,000

Trillion

12

1,000,000,000,000

Quadrillion

15

1,000,000,000,000,000

Quintillion

18

1,000,000,000,000,000,000

Sextillion

21

1,000,000,000,000,000,000,000

Septillion

24

1,000,000,000,000,000,000,000,000

Octillion

27

1,000,000,000,000,000,000,000,000,000

Nonillion

30

1,000,000,000,000,000,000,000,000,000,000

Ten: 10 (1 zero)
Hundred: 100 (2 zeros)
Thousand: 1000 (3 zeros)
Ten thousand 10,000 (4 zeros)
Hundred thousand 100,000 (5 zeros)
Million 1,000,000 (6 zeros)
Billion 1,000,000,000 (9 zeros)
Trillion 1,000,000,000,000 (12 zeros)
Quadrillion 1,000,000,000,000,000 (15 zeros)
Quintillion 1,000,000,000,000,000,000 (18 zeros)
Sextillion 1,000,000,000,000,000,000,000 (21 zeros)
Septillion 1,000,000,000,000,000,000,000,000 (24 zeros)
Octillion 1,000,000,000,000,000,000,000,000,000 (27 zeros)
Nonillion 1,000,000,000,000,000,000,000,000,000,000 (30 zeros)
Decillion 1,000,000,000,000,000,000,000,000,000,000,000 (33 zeros)
Zeros Grouped in Sets of 3
The reference to the set of zeros is reserved for groups of three zeros, which means they are not relevant for small numbers. We write numbers with commaseparated sets of three zeros so that the value is easier to read and understand. For example, you would write one million as 1,000,000 instead of 1000000.
As another example, it is much easier to remember that a trillion is written with four sets of three zeros than it is to count 12 distinct zeros. While you might think this is too easy, just wait until you need to count 27 zeros for an octalion or 303 zeros for a centian.
Then you’ll be grateful that you only have to memorize nine and 101 sets of zeros.
How Many Zeros in a Million?
One Million

Number of zeros 6

1,000,000

One Billion

Number of zeros 9

1,000,000,000

Numbers With Very Large Numbers of Zeros
The number googol (termed by Milton Sirotta) has 100 zeros after it. Here’s what a googol looks like, written out with all of its zeros:
10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000
Numbers With Very Large Numbers of Zeros
The number googol (termed by Milton Sirotta) has 100 zeros after it. Here’s what a googol looks like, including all of its required zeros:
10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000
Do you think this number is big? How about googolplex, followed by zero’s googol. The googolplex is so large that it has yet to be of any meaningful use—it is larger than the number of atoms in the universe.1
How Many Zeros in a Billion?
Zero is the most important digit for making large numbers. Large numbers above 100,000 are groups of three zeros separated by commas.
There are six zeros in a million, nine in a billion, and 12 in a trillion.
Million and Billion: Some Differences
In the United States—as well as in science and finance around the world—one billion is 1,000 million, which is written as one followed by nine zeros. It is also called “minor scale”.
There is also a “long scale”, used in France and formerly used in the United Kingdom, in which one billion means one million million. According to this definition of a billion, the number is written one after the other with 12 zeros. The short scale and the long scale were described by the French mathematician Genevieve Guital in 1975.
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