Mutual Fund Calculator
Project your mutual fund growth with an initial investment plus regular monthly contributions at a given annual return rate.
Future Value
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Total Invested
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Total Gains
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What is Mutual Fund Calculator?
A mutual fund calculator projects the future value of your investment based on an initial lump sum plus ongoing monthly contributions, compounded at an assumed annual return. It separates your total invested capital from the gains generated by compounding, helping you visualize the power of consistent investing over time.
How to use
- 1 Enter your initial investment amount.
- 2 Enter your planned monthly contribution.
- 3 Enter the expected annual return rate (use historical averages as a guide).
- 4 Enter the number of years you plan to stay invested.
- 5 Review the future value, total invested, and total gains.
Formula
Example calculation
$10,000 initial investment, $500/month, 8% annual return, 20 years: FV ≈ $344,780. Total invested: $130,000. Total gains: $214,780 — more than 1.6× what you put in.
Frequently asked questions
What is a realistic mutual fund return?
Broad US stock index funds have historically returned 7%–10% annually over long periods (before inflation). Bond funds typically return 3%–5%. A balanced fund might average 5%–7%. Use a conservative rate for planning.
Does this account for expense ratios?
No. Mutual fund expense ratios reduce your effective return. Subtract the fund's expense ratio from your expected return. A fund with 1% expenses and 8% gross return effectively compounds at ~7%.
What about taxes on gains?
Gains in taxable accounts are subject to capital gains tax. Gains inside a Roth IRA or 401(k) grow tax-deferred or tax-free. This calculator shows pre-tax figures.
How does starting early affect results?
Compounding rewards time dramatically. Investing $500/month for 30 years at 8% produces about $745,000 vs. $344,000 for 20 years — 10 extra years nearly doubles the result while only adding $60,000 more in contributions.
Should I use lump sum or monthly contributions?
Both strategies have merit. Lump-sum investing historically outperforms dollar-cost averaging about two-thirds of the time because money is invested sooner. Monthly contributions reduce timing risk and build the habit of regular saving.