Doubling Time Calculator
Find how long constant compound growth takes to double.
Formula
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations retain full precision.
Example Calculation
- Growth rate: 5 % / period
At 5% growth per period, doubling takes approximately 14.21 periods.
Frequently asked questions
How do I use this calculator?
Enter growth rate. The result updates automatically. Use Reset to restore the example values.
What method does it use?
Doubling time = ln(2) / ln(1 + r). Follow the units and definitions shown with the inputs to apply this relationship consistently.
Why might a rounded result differ?
The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.
Are my inputs saved online?
No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.
Check the assumptions and units before using this result. Read about calculation methods.