Compound interest calculator

Project the long-term growth of your investment by combining your starting capital, your regular contributions and the snowball effect of compound interest.

The money you begin with today.

How much you add every month, consistently.

%

Raise your contribution each year, e.g. as your salary grows. Leave 0 if fixed.

%

Estimated yearly return. Global equities have historically returned around 7-8% a year.

How many years you stay invested.

Estimated final value

$108,224

Total contributed

$49,000

Interest earned

$59,224

55% of the total is interest

Total valueContributed

Year-by-year breakdown

YearCumulative contributedCumulative interestTotal value
1$3,400$151$3,551
2$5,800$486$6,286
3$8,200$1,019$9,219
4$10,600$1,764$12,364
5$13,000$2,736$15,736
6$15,400$3,952$19,352
7$17,800$5,430$23,230
8$20,200$7,188$27,388
9$22,600$9,246$31,846
10$25,000$11,627$36,627
11$27,400$14,353$41,753
12$29,800$17,450$47,250
13$32,200$20,944$53,144
14$34,600$24,864$59,464
15$37,000$29,241$66,241
16$39,400$34,109$73,509
17$41,800$39,501$81,301
18$44,200$45,457$89,657
19$46,600$52,017$98,617
20$49,000$59,224$108,224

What if you pick better stocks?

The return you enter here depends on the stocks you choose. STKtracker helps you find solid companies and avoid value traps, so your snowball grows on firm ground.

Analyse stocks for free

What is compound interest?

Compound interest is the process by which the returns on your investment generate further returns of their own. Instead of always earning on your starting capital, each year you also earn on the interest accumulated in previous years. Over time this "snowball" effect makes growth accelerate.

That is why time is the most powerful factor when investing: the earlier you start and the more consistent your contributions, the larger the share of your final wealth that comes from interest rather than from your own pocket.

How to use the calculator

Enter your starting capital, how much you plan to add each month and the average annual return you expect. You can add an annual contribution increase to reflect saving more as your income grows.

The calculator assumes contributions and returns are reinvested, and shows the result year by year in a chart and a table so you can see when compound interest starts to make the difference.

This tool is for educational and informational purposes only. Past performance does not guarantee future results. It is not financial advice or a recommendation to buy or sell. Investing involves risk of loss.

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