The direct answer

A billion has 9 zeros: 1,000,000,000 = 109.

A billion is 1,000 million. In the modern English short scale used here, every step from million onward multiplies the previous named number by 1,000.

See the zeros in groups of three

1Billion
000zero group
000zero group
000zero group

Start with the 1 and count the zero groups to its right. Each complete group contributes three zeros, so 3 groups × 3 zeros = 9 zeros.

Previous and next named numbers

PositionNameWritten numberPower
Previousmillion1,000,000106
Currentbillion1,000,000,000109
Nexttrillion1,000,000,000,0001012

Each move to the right multiplies the number by 1,000 and adds three zeros.

How to say and write billion

The number 1,000,000,000 is written in words as one billion. A number such as 2,000,000,000 is two billion; the scale word itself does not become plural inside a number name.

Short-scale note: Big Number Playground uses the modern English short scale, where billion is 109 and each new “illion” is 1,000 times the previous one.

Use the Big Number Explorer to convert any whole number to words, or continue with the large number names chart and the million, billion and trillion comparison.