Numbers of Zeros in a Million, Googol , Billion, Trillion, and More

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.

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.

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 mind-boggling 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.

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 comma-separated 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.

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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