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How Many Zeros in a Billion? A Million? A Trillion?


Wondering how many zeros are in a billion? A trillion? A nonillion?

Whether you’ve recently won the lottery and are trying to make sure your bank account has the correct number of zeros or you’re simply trying to find an easy way to understand how many zeros are in large numbers (over a million), this is the article for you.

We’ll break down an easy trick for figuring out how many zeros are in large numbers and provide a handy chart for easy reference.


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 is, the more zeros it has.

Starting at 1,000, large numbers have groups of 0s in them. Every time you jump up to the next level of number, another 0 is added.

The number one thousand has three 0s in it (1,000). The number 10,000 has four 0s in it (10,000). The number one hundred thousand has five 0s in it (100,000). The number one million has six 0s in it (1,000,000).

Every time you have a full group of three zeros, like in one million (1,000,000), you use a comma to separate them.



How Many Zeros in a Million? How Many Zeros in a Billion? Reference Chart

Here’s how numbers from 100,000 to 1,000,000,000,000,000,000,000,000,000,000 (nonillion) look when written out with the correct groups of three 0s.

Number of Zeros
Written Out
One Thousand
Ten Thousand
One Hundred Thousand
One Million


How to Figure Out How Many Zeros in a Million

Trying to figure out how many zeros should be in a large number?

Each large number always adds a zero to the number immediately preceding it, starting at 1,000.

1,000 has three zeros. That means that the next large number, ten thousand (10,000), has four zeros.

The same goes when you get into the millions. One million has six zeros (1,000,000). Ten million has seven zeros (10,000,000). One hundred million has eight zeros (100,000,000).

When you make the jump from one large number to the next designation (for instance, from one million to one billion), you’ll add a group of three zeros. One million has six zeros (1,000,000), while one billion has nine zeros (1,000,000,000).


Recap: How Many Zeros in a Billion?

Zero the most important digit for creating large numbers. Large numbers above 100,000 have groups of three zeros separated by commas.

A million has six zeros, a billion has nine, and a trillion has 12.


What’s Next?

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Hayley Milliman
About the Author

Hayley Milliman is a former teacher turned writer who blogs about education, history, and technology. When she was a teacher, Hayley's students regularly scored in the 99th percentile thanks to her passion for making topics digestible and accessible. In addition to her work for PrepScholar, Hayley is the author of Museum Hack's Guide to History's Fiercest Females.

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