Mutual Fund Calculator

Estimate fund growth after fees

This calculator estimates what a hypothetical fund investment is worth after sales charges and annual operating expenses, and shows how much of the gap to a fee-free outcome came from fees. You enter a starting amount, optional yearly and monthly contributions, a holding length, a return and the fees. Everything is a fixed scenario you control; nothing is read from a prospectus.

The return field is labelled gross because it should be the return before fund expenses. Published figures are sometimes already net of expenses, in which case the expense ratio is part of the number you have. Entering such a figure and then also entering the expense ratio would charge the fee twice, so check the definition at the source first.

Amounts here are plain magnitudes in whatever currency you think in. The page adds no tax, no inflation and no fee waivers, and it uses no live prices, so it works as a what-if tool for the fee assumptions you type rather than a quote for a specific fund.

Front-end and deferred sales loads

A front-end sales charge is taken from money as it goes in. Here it is applied to each gross contribution: with a 2% charge, a 1,000 contribution puts 980 to work and 20 goes to the charge. The initial investment is treated the same way. A 100% charge leaves nothing invested, and the page handles that case without error.

A deferred sales charge is taken when money comes out. This model applies it once, at the end of the holding period, to the lesser of the total gross contributions and the balance just before exit, so the base can never be negative. With 5% on a balance that fell from 10,000 to 5,000, the base is 5,000 and the charge is 250.00, leaving 4,750.00. Real funds may charge on specific lots or use a schedule that declines each year; that detail is not modelled.

With a holding length of zero months nothing is invested for any time, but the loads still apply: 100 invested with a 10% front charge and a 5% deferred charge ends at 85.50.

To see what a front load means in money, a 5.75% charge on a 1,000 purchase leaves 942.50 invested and takes 57.50 immediately. That money never earns a return, which is why a load matters more on a short holding period and less on a long one, where it is a one-off cost spread across many years of growth.

Expense ratio and monthly fee timing

The annual operating expense is taken in twelve monthly steps. Each month the balance first grows by the monthly equivalent of the gross annual return, then one twelfth of the annual expense rate is deducted from the grown balance, then any end-of-month contribution is added. This is an illustrative accrual of the entered ratio, not the exact way a fund charges it.

Take 10,000 for one year at a 10% gross return with a 1% expense ratio. Month by month the model ends at 10,890.50. The operating expenses charged along the way total 104.85, and the gross gain is 995.35. A shortcut that simply subtracts the expense ratio from the return, 10% - 1% = 9%, gives 10,900.00 instead. The 9.50 difference comes from charging the fee on the grown balance every month rather than deducting one flat percentage from the year's return. The page uses the monthly model and says so; it does not claim to match every other calculator.

Small ongoing differences become large over decades. Take 10,000 for 30 years at a 7% gross return with no loads. A 0.5% expense ratio ends at 65,517.24, while a 1.5% expense ratio ends at 48,524.22. One extra percentage point of annual cost removes 16,993.02, and most of that difference is compounding, not the fees themselves.

Direct fees versus their growth effect

Two numbers describe the cost of fees, and they are not the same. Direct fees are what was actually charged: loads plus operating expenses. The fee impact is how much lower your ending value is than the same investment with no fees at all. In the one-year example the no-fee ending value is 11,000.00, so the fee impact is 109.50 while the direct fee was 104.85.

The remaining 4.65 is the growth effect: money taken as fees would have earned returns for the rest of the period. The page calls it the growth effect of fees rather than lost growth because the sign can flip. In a falling market, fees taken early also avoid later losses, so the effect can be negative. The identity that ties everything together is simple: gross contributions, minus front loads, plus gross gain, minus operating expenses, minus the deferred charge, equals the ending value.

It also helps to see fee impact as a share of the outcome. In the default case the fee impact of 3,328.20 is 3.57% of the no-fee ending value of 93,339.37. That share grows with the holding period and with the expense ratio, and it shrinks as loads become a smaller part of a larger balance.

Monthly and annual contributions

The page's default case invests 20,000 and adds 1,000 a month for five years, a gross contributed principal of 80,000. At a 5% gross return, a 2% sales charge and a 0.5% expense ratio the ending value is 90,011.17. Front loads take 1,600.00, operating expenses take 1,328.78 and the gross gain is 12,939.95.

You can also add a yearly contribution. At the end of each period it lands in months 12, 24 and so on; at the beginning of each period it lands in months 1, 13 and so on. With a yearly 1,200 and a monthly 100 over 24 months, both timings contribute 4,800.00, and at a 2% load the front loads are 96.00. The timing matters when returns are not zero, because money added earlier grows for longer. The complete monthly ledger lists every contribution, load, gain and expense, and the CSV export contains the same table.

Contribution timing matters even without fees. Investing 12,000 at the start of each year for ten years at a 5% gross return ends at 158,481.45, while investing 1,000 at the start of each month ends at 154,992.06. Both contribute 120,000, but the yearly lumps are invested earlier on average, so they end 3,489.39 higher. Enter the contribution pattern you would really follow before comparing fee scenarios, so that timing does not blur the effect of fees.

Compare two fee scenarios

Switch on the comparison to run a second set of fees against the same return, contributions, timing and horizon. Only the loads and the expense ratio change, so any difference in the result comes from fees alone. Counting it as one comparison, the page shows both ending values, both fee totals and the difference.

For example, 10,000 plus 100 a month for ten years at a 7% gross return ends at 31,539.97 with a 5.75% sales charge and a 1.2% expense ratio, and at 36,486.89 with no sales charge and a 0.1% expense ratio. The cheaper scenario ends 4,946.91 higher. That is an illustration of how fee assumptions compound, not a recommendation of any fund or share class.

The comparison can be split into its parts. Between the two scenarios the direct charges differ by 3,384.60, made up of 1,265.00 in front loads and 2,119.60 in operating expenses. The rest of the 4,946.91 difference in ending value is the growth effect: money the higher fees took and that therefore never compounded.

Net IRR, total gain and model limits

The net IRR treats your gross contributions as money paid in on their dates and the ending value after all fees as money received at the end, then solves for the yearly rate that balances them. For the default case it is 3.820% a year, below the 5% gross return because fees reduced the outcome. The total gain is the ending value minus the gross contributions, 10,011.17 here.

With a holding length of zero months the IRR is not available, and if nothing is ever returned there is no finite rate. A deferred charge case with 5% on the yearly-contribution example leaves 28,506.11 and a charge of 1,250.00. The model leaves out taxes, fee waivers, share-class conversions, transaction costs and distributions. To separate taxes and inflation scenarios, use the compound interest calculator; to compare lump sum and recurring investment timing, use the dollar cost averaging calculator; and to understand total and annualized ROI, use the ROI calculator. You can also test the cash flows of any scenario with the IRR calculator. A fund is not an insured deposit, so compare it with a guaranteed product only as a scenario, never as an equivalent.

Mutual fund fee questions