Compound Interest Calculator: Future Value + Growth Projection
See exactly how your money grows when returns compound on themselves. Enter your starting balance, monthly contributions, expected return, and time horizon to project your future wealth.
The lump sum you start with — savings already on hand or your initial deposit.
Recurring deposits each month. Set to $0 if you only want to project the principal.
Expected annual return. S&P 500 historical avg ~10%; conservative bond mix ~5-7%.
How long you plan to leave the money invested before drawing it down.
Total value at the end of the investment period — principal + contributions + compounded interest.
How is Compound Interest Calculator helpful?
Most hosts guess their numbers. Pros use data. This tool helps you make unemotional, data-driven decisions about your property portfolio, ensuring every dollar you invest yields a measurable return.
Accuracy
Based on real-time market data from 50+ cities.
Speed
Get answers in seconds, not hours of spreadsheet work.
Confidence
Bank-grade formulas used by institutional investors.
How the Compound Interest Calculator Works
This calculator breaks down your estimate using key inputs. Each one refines the output.
Initial Investment
Your starting lump sum ready to deploy
This capital starts compounding immediately, giving it the longest runway to generate returns on returns.
Monthly Contribution
Recurring deposits added each month
Regular contributions accelerate growth dramatically—even modest monthly amounts compound into significant wealth over decades.
Annual Return Rate (%)
Expected yearly investment return
Small differences in return rates create massive gaps over time due to compounding; a 1% difference can mean 25% less wealth over 30 years.
Turn projections into actual portfolio growth
Connect your accounts to track real compound growth against these projections and optimize your contribution strategy.
No credit card required
Frequently Asked Questions
What return rate should I use for my projections?+
The S&P 500 has historically averaged around 10% annually, but using 7-8% provides a margin of safety. Conservative bond-heavy portfolios typically return 4-6%. Use your expected return net of any management fees.
Does this calculator account for inflation?+
No. A 10% nominal return with 3% inflation is really a 7% real return. Either use real (inflation-adjusted) returns in your calculation, or mentally discount your future value by 2-3% annually when planning purchasing power.
How does this handle taxes on investment gains?+
The calculator shows pre-tax growth. Tax-advantaged accounts like 401(k)s and IRAs compound the full amount, while taxable brokerage accounts may owe capital gains taxes that reduce your actual balance by 20-30%.
Why does a small fee difference matter so much?+
A 1% annual fee compounds against you for decades. On a portfolio averaging 7% returns, that 1% fee can reduce your final balance by 25-30% over 30 years. Always use return rates net of fees.
How accurate are these projections?+
The calculator shows average compound growth, not the volatility you'll actually experience. Markets don't deliver steady returns—you might see -20% one year and +25% the next. Use this for planning direction, not precise predictions.
Should I revisit this calculation over time?+
Yes. Your contribution capacity typically increases as income grows. Revisit annually and increase contributions when you get raises or pay off debts to accelerate your timeline.