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Mutual Fund Calculator

Model fund growth · Compare expense ratios · Find the break-even hurdle

Fund Details

Final Balance (after fees)
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Total Contributions
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Total Gross Gains
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Fee Drag lost to fees
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Growth Comparison
Your Fund Zero-Cost Benchmark
Fund A
Fund B
Fund C
Switching from — to — would save — over 30 years.
Fund Expense Ratio Final Balance Fees Paid Net Gain
Fund Comparison
Net Gain Fee Drag

Inputs

Annual Outperformance Needed to Break Even
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per year, every year
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● Easy (<0.5%) ● Moderate (0.5–1%) ● Hard (>1%)
At 0% outperformance, active fund costs you — over 20 years.
Performance Divergence
Index Fund Active @ 0% alpha Active @ break-even alpha

HOW TO USE

01

Enter Fund Details

In the Fund Growth tab, enter your initial investment, monthly contribution, expected gross return, and the fund's expense ratio.

02

See the Fee Drag

Watch the Fee Drag card update in real time. The dual-line chart shows the gap between your fund and a zero-cost benchmark — growing wider every year.

03

Compare Funds

Switch to Fund Comparison to compare up to 3 funds side-by-side and see the stacked bar showing how much of each fund's return disappears to fees.

What does an expense ratio actually cost you?

A 1% expense ratio sounds small but compounds massively. On $10,000 growing at 7% gross for 30 years: a 0.03% index fund grows to ~$75,300 while a 1% fund only reaches ~$57,400 — a $17,900 difference. You paid the fund manager nearly $18,000 to likely underperform the index.

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Frequently Asked Questions

BasicsWhat is an expense ratio and how is it charged?
An expense ratio is the annual percentage of fund assets charged to cover operating costs (management fees, administrative costs, marketing). A 0.5% expense ratio means you pay $50 per year on a $10,000 investment. It is deducted daily from fund NAV — you never see a bill. Low-cost index funds charge 0.03%–0.10%, while actively managed funds typically charge 0.5%–1.5%.
StrategyWhy does a small expense ratio matter so much over time?
Because you lose not just the fee dollars, but all the future compound growth those dollars would have generated. A 1% fee on a 7% gross return reduces your net return to 6% — a 14% reduction in growth rate. Over 30 years this difference compounds into tens of thousands of dollars on a modest initial investment.
BasicsWhat is the difference between an index fund and an active fund?
Index funds passively track a benchmark (like the S&P 500) by holding all or most of its constituent stocks. With minimal trading and no research team, costs stay extremely low (0.03%–0.10%). Active funds employ portfolio managers who research and select stocks, aiming to beat the market. Their higher operating costs result in expense ratios of 0.5%–1.5%. Research consistently shows that >80% of active funds underperform their benchmark index over 15+ year periods after accounting for fees.
AdvancedWhat is the break-even hurdle rate?
The break-even hurdle is the minimum annual gross outperformance an active fund must generate to match a low-cost index fund after both fees are applied. It equals Active Expense Ratio − Index Expense Ratio. A fund charging 1.0% vs. an index at 0.03% must outperform the index's gross return by 0.97% every single year — a feat most active managers fail to sustain over a decade.
BasicsWhat is a fund load, and should I avoid it?
A load is a sales commission charged by a broker or financial advisor at purchase (front-end load, e.g. 5%) or at sale (back-end/deferred load). A 5% front-end load means you invest only $9,500 of every $10,000. No-load funds are available directly from fund companies (Vanguard, Fidelity, Schwab) with no sales commission. Expense ratios are a separate, ongoing cost regardless of loads.
AdvancedHow does this calculator model after-tax returns?
When you enter a tax rate, the calculator applies it only to investment gains (not the return of your contributions). This models a simplified taxable account where all gains are eventually taxed at your marginal rate. For tax-advantaged accounts (401k, IRA, Roth), set the tax rate to 0. Note: this simplified model doesn't account for annual dividend distributions or the specifics of long-term vs short-term capital gains rates.
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Formula & Methodology

Net Return Rate

Net Rate = Gross Return Rate − Expense Ratio

The expense ratio directly reduces your annual return. At 7% gross with a 0.5% expense ratio, your net return is 6.5%.

Future Value with Contributions

FV = PV × (1 + r/12)12n + PMT × [((1 + r/12)12n − 1) / (r/12)]

Where PV = initial investment, r = annual net rate, n = years, PMT = monthly contribution. The calculator compounds monthly for accuracy.

Fee Drag

Fee Drag = FV(expense=0) − FV(your expense ratio)

The dollar difference between growing at the full gross rate and growing at the net rate. This gap widens exponentially over time as compounding amplifies every lost dollar.

Break-Even Hurdle Rate

Hurdle = Active ER − Index ER

The active fund manager must beat the index's gross return by this percentage every year, indefinitely, just to tie the index fund after fees.

About this calculation · Accuracy & Methodology

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Key Terms Explained

Expense RatioAnnual percentage of fund assets charged as fees. Deducted daily from NAV. Includes management, administrative, and marketing costs.
NAVNet Asset Value — the per-share price of a mutual fund, calculated as (total assets − liabilities) ÷ shares outstanding. Updated daily after market close.
Fee DragThe cumulative wealth lost due to expense ratios. Includes both the direct fee dollars and all future compound growth those dollars would have generated.
Index FundA passively managed fund that tracks a market index (S&P 500, Total Market, etc.) at minimal cost. Characterized by broad diversification, low turnover, and expense ratios as low as 0.03%.
Active FundA fund managed by portfolio managers who select securities to beat a benchmark. Higher research and trading costs result in expense ratios of 0.5%–1.5%+.
Fund LoadSales commission paid when buying (front-end load) or selling (back-end load) a mutual fund. Separate from the expense ratio. No-load funds charge no commission.
Turnover RateThe percentage of a fund's holdings replaced in a year. High turnover increases trading costs and tax liability. Index funds typically have <5% turnover; active funds often exceed 50%.
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Real-World Examples

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David

30-Year Cost of a 1% Expense Ratio

Setup: $10,000 initial, $500/mo contributions, 7% gross return, 30 years.
Index Fund (0.03%): Final balance ≈ $605,800. Fees paid ≈ $500.
Active Fund (1.00%): Final balance ≈ $497,600. Fees paid ≈ $108,700.
Verdict: The 1% expense ratio costs David over $108,000 in fees — more than his entire initial investment 10x over.

Expense Ratio Impact at $10,000 Over 30 Years (7% Gross)

Expense RatioNet ReturnFinal BalanceFees PaidFee Drag vs 0.03%
0.03% (Index)6.97%$74,800~$100—
0.25%6.75%$71,100~$3,700$3,700
0.50%6.50%$67,400~$7,400$7,400
1.00%6.00%$57,400~$17,400$17,400
1.50%5.50%$48,900~$25,900$25,900
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The Hidden Cost of High Expense Ratios Over a Career

The Silent Drain

Expense ratios are invisible in a way that makes them uniquely dangerous. You never receive a fee invoice. The fund simply grows a little more slowly every day. At 0.5%, you might not notice anything after one year. After 30 years, you've silently surrendered a substantial fraction of your potential wealth.

Compounding as a Fee Amplifier

The insidious math: every dollar of fees paid today is a dollar that won't compound for the remaining years of your investment horizon. A $100 fee paid in year 1 on a 7% portfolio actually costs you $100 × (1.07)^29 ≈ $700 in final wealth at the 30-year mark. Fees in early years are far more destructive than fees in later years — which is exactly why starting in low-cost funds matters most when you're young.

The Active vs. Passive Reality

The investment industry has spent decades arguing that skilled managers can justify high fees through superior performance. The data disagrees. S&P's SPIVA Scorecard consistently shows that over 15-year periods, over 85% of actively managed U.S. equity funds underperform their benchmark index on a net-of-fees basis. The funds that do outperform rarely sustain that alpha, and identifying them in advance is effectively impossible. Nobel laureate William Sharpe mathematically proved that the average active manager must underperform the average index fund by exactly the cost difference — it is arithmetic, not opinion.

When Fees Matter Most

The fee drag is greatest when: (1) your investment horizon is long, (2) expected returns are moderate (lower gross returns give fees a larger proportional bite), and (3) you have large assets (absolute dollar fees scale with portfolio size). In a taxable account, the additional tax cost of actively managed funds' higher turnover rates adds another layer of drag not captured in the expense ratio alone.