## How Much Is A Billion?

### Understanding The Federal Budget: What Is A Billion?

Politicians — at the state and federal level — talk in numbers that most folks can’t visualize.

How much is a billion? What does it mean to say that something costs a billion dollars ($1B)?

First, we have to clarify that we’re using the US system of numbers, not the British system (short scale v long scale). If we’re talking about things relating to the US political system, we are using the US system. Here’s the math:

1 Thousand | 1,000 | 10^{3} |

1 Million | 1,000,000 | 10^{6} |

1 Billion | 1,000,000,000 | 10^{9} |

1 Trillion | 1,000,000,000,000 | 10^{12} |

1 Quadrillion | 1,000,000,000,000,000 | 10^{15} |

1 Quintillion | 1,000,000,000,000,000,000 | 10^{18} |

The chart, however accurate, doesn’t put the number “a billion” — one thousand million — into perspective. Most of us know that the numbers are **big**, we just don’t know how to think of them in the context of our own lives. Here are some attempts, collected from around the Net:

- If we wanted to pay down a billion dollars of the US debt, paying one dollar a second, it would take 31 years, 259 days, 1 hour, 46 minutes, and 40 seconds. To pay off a trillion dollars of debt, at a dollar a second, would take about 32,000 years. The current U.S. federal debt is $13.2 trillion.
- About a billion minutes ago, the Roman Empire was in full swing. (One billion minutes is about 1,900 years.)
- About a billion hours ago, we were living in the Stone Age. (One billion hours is about 114,000 years.)
- About a billion months ago, dinosaurs walked the earth. (One billion months is about 82 million years.)
- A billion inches is 15,783 miles, more than halfway around the earth (circumference).
- A person counting at the rate of two numbers per second would need 5 years, 308 days, 9 hours, 41 minutes, 50 seconds to reach a billion.
- The earth is about 8,000 miles wide (diameter), and the sun is about 800,000 miles wide, not quite a
*million*.

Remember that a trillion is one thousand billion — and today’s federal budget numbers are in trillions.

For a really mind-blowingly large number, think about the googol, which is 1 followed by 100 zeros (10^{100}). To try to wrap your mind around that, envision a diamond that weighs as much as the earth. It would contain only 10^{50} carbon atoms.

*I originally **wrote this article for About.com** in 2004.*

Thanks, Nathan!

A really mind-blowing number is Googolplex; ten to the power of googol, Which is ten to the power of ten to the power of one hundred.