Tools · Calculator
Compound growth calculator
See how a starting amount grows at a fixed yearly rate you choose, year by year, with an optional amount added each year.
An illustration, not a forecast. This calculator applies a fixed growth rate you choose. Real-world growth isn't steady and can be negative; the result shows how compounding works, nothing more.
The formula
Ending amount = starting amount × (1 + rate)years
Doubling time (rule of 72) ≈ 72 ÷ rate in percent
With an amount added at the end of each year, the calculator grows the running total one year at a time and adds the amount after each year's growth.
Why compounding matters
At a steady rate, the amount added each year keeps getting bigger, because the rate applies to a bigger base. That's why small differences in a rate add up over long periods: at 1,000 for 30 years, 5% a year ends near 4,322 and 7% a year near 7,612.
Going the other way
To find the steady yearly rate between two numbers you already have, such as a company's revenue three years apart, use the growth rate calculator. It loads figures from 10-K filings.
Common questions
What is compound growth?
Growth that builds on itself: each year's growth is worked out on the amount at the start of that year, including earlier growth. At 5% a year, 1,000 becomes 1,050 after one year and 1,102.50 after two, not 1,100.
What is the formula for compound growth?
Ending amount = starting amount × (1 + rate) ^ years, with the rate as a decimal. 1,000 growing at 5% for 10 years is 1,000 × 1.05^10, about 1,628.89.
What is the rule of 72?
A shortcut for doubling time: divide 72 by the yearly growth rate in percent. At 6% a year, an amount doubles in about 12 years. It's close for rates between about 2% and 15%.
How is this different from CAGR?
CAGR runs the formula backwards: it starts from a beginning and an ending value and finds the steady yearly rate between them. The growth rate calculator does that.
Can I use this to predict returns?
No. The calculator applies a fixed rate you choose. Real growth rates change from year to year and can be negative, so the result is an illustration of the arithmetic, not a forecast.
Disclosures
- Editor holdings
- The editor holds no position in any company named on this page. As of Oct 25, 2026.
- Compensation
- Nobody paid for this calculator. No affiliate links on this calculator.
- Sources
- Each company's own SEC filings, linked next to each number.
- Last updated
- Oct 26, 2026
General education, the same for every reader. Not a recommendation to buy, sell or hold any security, and it doesn't consider your situation.
More in Learn and Tools · Methodology & Disclosures explains where every number comes from.