See how monthly contributions and compound interest can grow your investments over time.
See how monthly contributions and compound interest can grow your investments over time.
Albert Einstein famously called compound interest the most powerful force in the universe. It is the process where your earnings generate their own earnings, leading toexponential growth that can turn modest savings into a fortune over time.
In the beginning, your contributions do 99% of the work. But eventually, you reach a "Critical Mass" where your investment returns exceed your annual contributions. This is when your wealth starts to explode. Our simulator helps you visualize exactly when you'll hit that tipping point.
Divide 72 by your interest rate to see how many years it takes to double your money. At 7%, it's about 10 years.
Starting 10 years earlier is often more effective than doubling your monthly contribution later in life.
Use the calculator to see your projected final value, how much comes from your own contributions, and how much comes from investment growth. The chart updates instantly as you change your monthly contribution, timeframe, or expected return.
Beginner tip: Start with a realistic monthly amount, then compare 5%, 7%, and 10% annual returns to see how compounding changes the long-term result.
Disclaimer: Wealth Sim is an independent educational tool for financial simulation and is not affiliated with any financial institution, including Wealthsimple. All calculations are for educational purposes and do not constitute financial advice.
Common questions about compound interest and investment calculations
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Instant answer
If you invest $1,000 upfront and $200/month for 20 years at a 7% annual return, you could reach about $102,276.
You put in $49,000. Growth adds about $53,276. Fees reduce the result by about $4,078.
Millionaire path
To aim for $1,000,000 in 20 years, try about $1,912/month.
Final Value
$102,276
Total wealth
Total Invested
$49,000
Your contributions
Interest Generated
$53,276
108.73% return
Total Fees Paid
$4,078
You could lose $4,078 to fees over 20 years.
Worth in today's purchasing power:
$62,416
This is what your final balance would be worth in today's money
Nominal value in future dollars:
$102,276
In 20 years at 2.5% annual inflation
Why the difference? Due to 2.5% inflation, your $102,276 in 20 years will have the same purchasing power as $62,416 today. This means goods and services that cost $62,416 today will cost $102,276 in the future.
Last updated: 2026-04-19
Management fees are deducted from the annual rate before compounding (net rate = r − fee). When "Real Return" is enabled the inflation rate is also subtracted so results are expressed in today's purchasing power.
Growth is taxed annually at the capital gains rate specified in the inputs. Tax is applied to the nominal gain each year before compounding continues.
Disclaimer: wealthsim is a free simulation tool for educational purposes only. Results are estimates based on the inputs you provide and simplified tax modelling. They do not constitute financial, tax, or investment advice. Consult a qualified financial advisor before making investment decisions. wealthsim is not affiliated with or endorsed by Wealthsimple Inc.
Explore more financial calculators to help you plan your investment strategy
Project S&P 500 growth from monthly contributions using a historical return benchmark.
Model dividend reinvestment with 2–4% yields and see how compounding affects long-term returns.
Estimate how your retirement savings can grow from monthly contributions and long-term returns.