Quick answer
Net return = expected return − expense ratio, and FV = P(1 + i)^m + C × ((1 + i)^m − 1) ÷ i with i = net return ÷ 12. $10,000 plus $200 a month at 7% with a 1% expense ratio for 20 years grows to $125,510.22, against $144,572.72 with no fees: fees cost $19,062.50.
Enter the initial investment, monthly contribution, expected return, expense ratio and years. The calculator returns the value after fees, without fees and the cost of fees. Use this mutual fund calculator to check your own figures.
Related tools: Investment Calculator: Project investment growth from a rate of return you choose. Financial Calculator: Time-value-of-money solver for N, rate, present value, payment or future value. IRR Calculator: Internal rate of return of an investment from its yearly cash flows.
How to use the Mutual Fund Calculator
- Enter initial investment ($) (0 or more).
- Enter monthly contribution ($) (0 or more).
- Enter expected annual return (before fees) (%) (between 0 and 100).
- Enter expense ratio (%) (between 0 and 100).
- Enter years (between 0 and 100).
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Initial investment | A number, in $ | ≥ 0 |
| Monthly contribution | A number, in $ | ≥ 0 |
| Expected annual return (before fees) | A number, in % | ≥ 0, ≤ 100 |
| Expense ratio | A number, in % | ≥ 0, ≤ 100 |
| Years | A number | > 0, ≤ 100 |
Formula and method
Formula
net return = return − expense ratio; FV = P(1 + i)^m + C × ((1 + i)^m − 1) ÷ i, i = net return ÷ 12
IEEE-754 double precision; money shown to cents, rates to 4 decimals. Results are estimates, not financial advice.
Monthly compounding with end-of-month contributions. Sales loads and taxes are excluded.
Worked examples
These examples are verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Initial investment = 10000; Monthly contribution = 200; Expected annual return (before fees) = 7; Expense ratio = 1; Years = 20.
| Result | Value |
|---|---|
| Value after fees | $125,510.22 |
| Value with no fees | $144,572.72 |
| Cost of fees | $19,062.50 |
Example 2
Inputs: Initial investment = 5000; Monthly contribution = 0; Expected annual return (before fees) = 8; Expense ratio = 0.5; Years = 10.
| Result | Value |
|---|---|
| Value after fees | $10,560.32 |
| Value with no fees | $11,098.20 |
| Cost of fees | $537.88 |
The first line is the headline result (value after fees). Below it the mutual Fund Calculator lists value with no fees and cost of fees, which describe the same case from other angles. IEEE-754 double precision; money shown to cents, rates to 4 decimals. Results are estimates, not financial advice.
Fees compound
A 1% annual fee sounds small, but it comes out of the growth every year. Over 20 years it takes about 13% of the end value here. Comparing a 0.1% index fund with a 1% managed fund on the same return shows the gap.
Assumptions
The return is an assumption, not a promise, and real returns vary year to year. An expense ratio above the return gives a loss. Taxes, sales loads and inflation are not included.
How the result changes with initial investment
Holding every other input at the first worked example, this table changes only initial investment. It shows how sensitive the answer is to that one value; each row was produced by running this calculator.
| Initial investment | Value after fees | Value with no fees | Cost of fees |
|---|---|---|---|
| 5000 | $108,959.20 | $124,379.03 | $15,419.82 |
| 10000 | $125,510.22 | $144,572.72 | $19,062.50 |
| 20000 | $158,612.27 | $184,960.11 | $26,347.84 |
| 40000 | $224,816.36 | $265,734.89 | $40,918.53 |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Years: entering "0" shows "Years must be greater than 0." beside that field and no result.
- Initial investment: entering "-1" shows "Initial investment must be at least 0." beside that field and no result.
Choosing between the Mutual Fund Calculator and similar calculators
Each row shows what a related calculator on this site asks for and what it returns, so you can pick the one that matches your question.
| Calculator | You enter | It returns |
|---|---|---|
| [Investment Calculator](/finance/investment-calculator/) | initial amount, annual interest rate and years | Projected value |
| [Financial Calculator](/finance/financial-calculator/) | solve for, periods per year and payments | Future value (FV) |
| [IRR Calculator](/finance/irr-calculator/) | initial investment and cash flows | IRR |
| [CAGR Calculator](/finance/cagr-calculator/) | beginning value, ending value and years | CAGR |
| [Present Value Calculator](/finance/present-value-calculator/) | future value, annual discount rate and years | Present value |
Background: interest, saving and investing
A nominal rate (APR) does not include the effect of compounding; the annual percentage yield (APY) does: APY = (1 + r/n)^n − 1. A 5% nominal rate compounded annually is 5.000%, semi-annually about 5.063%, quarterly about 5.095% and monthly about 5.116%, so more frequent compounding helps, but with diminishing returns.
The rate you enter in a projection is an assumption, not a promise: real returns vary and can be negative. Fees and taxes are not modelled unless the page says so.
Assumptions and limitations
- Expense ratio above the return gives a loss
Results are estimates for planning, not financial advice. Lender terms, fees, taxes and rounding rules can change real figures, so confirm important numbers with your lender or a licensed adviser.
If a required value is empty, not a number, or outside its allowed range, the form marks that field with a message and shows no result instead of a misleading number. The automated checks deliberately try invalid entries for years and initial investment to confirm this.
Frequently asked questions
What is an expense ratio?
The annual fund cost as a percentage of assets.
What is a low expense ratio?
Index funds charge 0.03% to 0.2%.
Does this predict my returns?
No, it is an illustration.
What does the Mutual Fund Calculator calculate?
Growth of a fund investment after its expense ratio. It returns Value after fees, Value with no fees and Cost of fees.
What formula does the Mutual Fund Calculator use?
net return = return − expense ratio; FV = P(1 + i)^m + C × ((1 + i)^m − 1) ÷ i, i = net return ÷ 12. Monthly compounding with end-of-month contributions.
What do I need to enter in the mutual Fund Calculator?
You enter Initial investment ($), Monthly contribution ($), Expected annual return (before fees) (%), Expense ratio (%) and Years.
How is the result rounded or limited?
IEEE-754 double precision; money shown to cents, rates to 4 decimals. Results are estimates, not financial advice. Expense ratio above the return gives a loss.
What is an example of a mutual Fund result?
With initial investment 10000, monthly contribution 200, expected annual return (before fees) 7, expense ratio 1 and years 20, the value after fees is $125,510.22.
Can I rely on this calculator for a decision?
Results are estimates for planning, not financial advice. Lender terms, fees, taxes and rounding rules can change real figures, so confirm important numbers with your lender or a licensed adviser. For this calculator in particular: Expense ratio above the return gives a loss.
Related calculators
- Investment Calculator — Project investment growth from a rate of return you choose.
- Financial Calculator — Time-value-of-money solver for N, rate, present value, payment or future value.
- IRR Calculator — Internal rate of return of an investment from its yearly cash flows.
- CAGR Calculator — Compound annual growth rate between two values.
- Present Value Calculator — Today's value of a future amount at a given discount rate.
- Net Present Value Calculator — NPV of an initial outlay and a series of yearly cash flows.
Sources
- Standard time-value-of-money relations (e.g. Brealey, Myers & Allen, Principles of Corporate Finance)
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.