Understanding your mutual fund projection
| Component | What it represents |
|---|---|
| Total invested | The sum of every monthly contribution made, with no growth applied |
| Investment gains | Growth generated by compounding at the net (after-expense-ratio) rate, on top of contributions |
| Value lost to expenses | The gap between what the same contributions would have grown to fee-free versus what they actually grow to net of the expense ratio |
- This projection assumes a constant monthly contribution and a constant annual return for the entire horizon; real markets do not deliver smooth, constant returns, so actual results will differ from this straight-line projection.
- The annuity-due assumption (contributions at the start of each month) is a modeling convention; a fund or plan that actually processes contributions at the end of the month would produce a very slightly lower maturity value.
- This is an educational projection based on the return and expense ratio assumptions entered, not a guarantee, prediction, or recommendation regarding any specific fund.
What is a mutual fund SIP calculation?
A systematic investment plan (SIP) is a strategy of contributing a fixed amount to a mutual fund at regular intervals — commonly monthly — rather than investing a single lump sum, allowing gains to compound on each contribution over the remaining investment horizon. This calculator treats each monthly contribution as occurring at the start of the month (an annuity-due pattern), a common convention for scheduled recurring investments.
The fund's net return used in the growth calculation is the gross expected annual return minus the annual expense ratio, reflecting the fact that expense ratios are deducted continuously from fund assets and therefore reduce the compounding rate an investor actually experiences, not just a one-time fee.
Because the expense ratio compounds alongside the investment itself over the full horizon, its total dollar cost — reported here as value lost to the expense ratio — can be substantial over long investment periods, even when the annual percentage looks small.
How to use this mutual fund calculator
- Enter the monthly contribution amount you plan to invest.
- Enter the expected gross annual return of the fund, before fees.
- Enter the fund's annual expense ratio.
- Enter the investment horizon in years.
- Read the projected maturity value, the total amount you actually contributed, the investment gains on top of contributions, and how much value the expense ratio is expected to cost over the horizon.
- Example: $500 per month at a 12% gross annual return with a 1.5% expense ratio (a 10.5% net return) over 10 years grows to approximately $106,330 at maturity.
The formula behind this SIP projection
The calculator first subtracts the expense ratio from the gross expected return to get a net monthly growth rate, then applies the future value of an annuity-due formula — which assumes each contribution is made at the beginning of its period rather than the end — to project the compounding balance across all contributions. The same calculation is repeated at the gross (fee-free) rate to determine how much value the expense ratio cost over the same horizon.
Common mistakes
- Using an unrealistically high gross return assumption, which compounds into an inflated maturity value that a real fund is unlikely to achieve consistently.
- Overlooking how much the expense ratio actually costs over a long horizon, since its effect is easy to underestimate when only the small annual percentage is considered in isolation.
- Forgetting that the maturity value includes both contributions and gains — mistaking the total maturity figure for the amount actually invested out of pocket.
- Assuming contributions and returns will be perfectly steady every month for the entire horizon, when actual mutual fund returns vary considerably year to year.
- Comparing two funds' projected maturity values without also comparing their expense ratios, since a lower gross return with a lower expense ratio can sometimes outperform a higher gross return with a higher expense ratio net of costs.
अक्सर पूछे जाने वाले सवाल
What is a systematic investment plan (SIP)?
A systematic investment plan is a strategy of investing a fixed amount into a mutual fund at regular intervals, commonly monthly, rather than as a single lump sum. This approach allows each contribution to begin compounding as soon as it is invested and is a common way to build a mutual fund position gradually over time.
How does the expense ratio reduce my mutual fund returns?
The expense ratio is deducted continuously from fund assets, which lowers the net return an investor actually experiences compared with the fund's gross (before-cost) performance. Because this reduced rate compounds over the entire investment horizon rather than being a one-time deduction, even a modest expense ratio can meaningfully lower the final maturity value over long periods.
Why does this calculator assume contributions happen at the start of each month?
This calculator uses the annuity-due convention, treating each monthly contribution as if it is invested at the beginning of the month rather than the end, which is a standard and commonly used modeling choice for scheduled recurring investments. It produces a maturity value very slightly higher than an equivalent end-of-month (ordinary annuity) calculation, since each contribution compounds for one additional month.
How much of my mutual fund's maturity value comes from my own contributions versus investment gains?
This calculator separates the two: total invested is simply the sum of every contribution made with no growth applied, while investment gains represent the additional value generated by compounding at the net (after-expense-ratio) return. The split between these two figures shows how much of the final balance came from your own money versus market growth.
Is the projected maturity value guaranteed?
No. This is a mathematical projection based on the gross return and expense ratio assumptions entered; actual mutual fund returns vary year to year and are never guaranteed to match a constant assumed rate. The projection is intended as an educational illustration of compounding and fee impact, not a forecast or promise of future performance.
संदर्भ
- U.S. Securities and Exchange Commission (SEC), Investor.gov. Mutual funds — systematic investing and dollar-cost averaging basics. investor.gov.
- Financial Industry Regulatory Authority (FINRA). Mutual fund fees, expense ratios, and their effect on returns. finra.org.
- CFA Institute. CFA Program Curriculum — Quantitative Methods: Time Value of Money and Annuities.
- U.S. Securities and Exchange Commission (SEC). Mutual Fund Fees and Expenses (Investor Bulletin). sec.gov.