# Doubling Time Calculator

## About Doubling Time Calculator

The Doubling Time Calculator is used to calculate the doubling time for a constant growth rate.

## Doubling Time Definition

In finance, the doubling time is the period of time required for an investment or money in an interest-bearing account to double in size or value. It is also applied to population growth, inflation, resource extraction, compound interest, and many other things that tend to grow over time.

## Doubling Time Formula

For a constant growth rate, the doubling time calculation formula is as follows:

T_{d} = log(2) / log(1 + r)

Where:

T_{d} = doubling time

r = a constant growth rate

## Doubling Time Table

Some doubling times calculated with the above formula are shown in the following table.

r% | T_{d} | r% | T_{d} | r% | T_{d} | r% | T_{d} | r% | T_{d} | r% | T_{d} | r% | T_{d} |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|

0.1 | 693.49 | 1.1 | 63.36 | 2.1 | 33.35 | 3.1 | 22.7 | 4.1 | 17.25 | 5.5 | 12.95 | 11 | 6.64 |

0.2 | 346.92 | 1.2 | 58.11 | 2.2 | 31.85 | 3.2 | 22.01 | 4.2 | 16.85 | 6.0 | 11.9 | 12 | 6.12 |

0.3 | 231.4 | 1.3 | 53.66 | 2.3 | 30.48 | 3.3 | 21.35 | 4.3 | 16.46 | 6.5 | 11.01 | 13 | 5.67 |

0.4 | 173.63 | 1.4 | 49.86 | 2.4 | 29.23 | 3.4 | 20.73 | 4.4 | 16.1 | 7.0 | 10.24 | 14 | 5.29 |

0.5 | 138.98 | 1.5 | 46.56 | 2.5 | 28.07 | 3.5 | 20.15 | 4.5 | 15.75 | 7.5 | 9.58 | 15 | 4.96 |

0.6 | 115.87 | 1.6 | 43.67 | 2.6 | 27 | 3.6 | 19.6 | 4.6 | 15.41 | 8.0 | 9.01 | 16 | 4.67 |

0.7 | 99.36 | 1.7 | 41.12 | 2.7 | 26.02 | 3.7 | 19.08 | 4.7 | 15.09 | 8.5 | 8.5 | 17 | 4.41 |

0.8 | 86.99 | 1.8 | 38.85 | 2.8 | 25.1 | 3.8 | 18.59 | 4.8 | 14.78 | 9.0 | 8.04 | 18 | 4.19 |

0.9 | 77.36 | 1.9 | 36.83 | 2.9 | 24.25 | 3.9 | 18.12 | 4.9 | 14.49 | 9.5 | 7.64 | 19 | 3.98 |

1.0 | 69.66 | 2.0 | 35 | 3.0 | 23.45 | 4.0 | 17.67 | 5.0 | 14.21 | 10 | 7.27 | 20 | 3.8 |