Investment Calculator
Project the future value of an investment that grows through both compounding and regular contributions. Set your starting balance, recurring deposit, expected return, and contribution frequency to see how much your portfolio could be worth and how much of that is growth versus what you put in.
How to Use
- Enter your initial investment — the lump sum you start with (use 0 if starting from scratch).
- Enter your recurring contribution and choose its frequency: monthly, quarterly, or annually.
- Enter your expected annual return as a percent and the number of years to grow.
- Choose timing — whether each contribution lands at the beginning or end of the period.
- Read the projected future value, total contributed, and total investment growth.
Show Work
Timing impact
About the Investment Calculator
Working on personal-finance and money decisions? The Investment Calculator is a free browser tool that gives you the answer in seconds. Project the future value of an investment that grows through both compounding and regular contributions. Set your starting balance, recurring deposit, expected return, and contribution frequency to see how much your portfolio could be worth and how much of that is growth versus what you put in.
How it works
Put each value in its box and read the answer as you go. Because it recalculates live, you can play with the inputs to see how each one moves the result — handy for checking your own working or planning ahead. Everything happens on your device, so it is fast and private.
Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.
Frequently Asked Questions
What annual return should I use?
For a diversified stock-heavy portfolio, 6%–8% is a common long-run planning assumption before inflation; more conservative or bond-heavy mixes run lower. These are not guarantees — markets are volatile year to year. Running a lower scenario alongside your base case is a healthy sanity check.
Does contribution timing really matter?
A little. Contributing at the beginning of each period (an "annuity due") gives every deposit one extra period of growth versus contributing at the end, so the ending balance is slightly higher. Over long horizons the difference compounds into a meaningful, though modest, amount.
Is this return before or after inflation?
The calculator uses the nominal return you enter, so the result is in future dollars. To see the real (today's-dollars) value of your portfolio, subtract your inflation assumption from the return — for example, an 8% return with 3% inflation is about 5% real growth.
Does it account for taxes and fees?
No — it shows gross growth at the rate you enter. Investment fees and expense ratios reduce returns, and taxes on gains, dividends, or withdrawals depend on the account type (taxable, Traditional, or Roth). Treat the output as an optimistic upper bound and an estimate, not advice.
How is the growth calculated?
The starting balance compounds at the periodic rate, and each contribution is treated as a series of deposits (an annuity) that also compounds until the end. The total return is the projected balance minus everything you contributed.
How do I use the Investment Calculator?
Simply type your numbers and read the result, which refreshes the instant you change something. There is nothing to submit and nothing to wait for.
Do I need to install or sign up for anything?
Not at all — it runs in the browser with nothing to install and no account. After it loads once, it even works without an internet connection.
Is my information private?
Yes. Everything happens in your browser. Nothing you type is sent to a server or saved anywhere.
Common Use Cases
Building a long-term portfolio
See how a steady monthly investment plus market growth compounds into a substantial balance over decades.
Maxing out an IRA
Model contributing the annual IRA limit each month and watch the projected balance at retirement age.
Lump sum vs. dollar-cost averaging
Compare starting with a large initial amount against building up through regular contributions.
Setting a savings rate
Work out the monthly contribution needed to reach a target portfolio value by a chosen year.
Visualizing growth vs. contributions
See how much of your ending balance is money you saved versus compound growth doing the heavy lifting.
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