What a fund's fee really costs over decades — the compounding drag, in dollars
| Years | Fund A | Fund B | Fee cost difference |
|---|
The expense ratio looks like rounding error — 0.75% versus 0.04% seems like nothing next to market swings of that size before lunch. But fees are the one part of investing that compounds against you with perfect reliability: charged on the whole balance, every year, in up markets and down. This calculator turns the innocuous percentage into what it actually is over an investing lifetime — routinely a six-figure difference on ordinary savings.
$50,000 plus $500/month at 8% gross for 30 years: at a 0.04% index-fund fee you finish with ~$1.02M; at a 0.75% active-fund fee, ~$885k. The fee difference — 0.71% per year — quietly consumed ~$135,000, about 13% of your final wealth. Nothing about markets, skill or luck: pure arithmetic.
| Product | Typical expense ratio |
|---|---|
| Broad index ETFs (S&P 500, total market) | 0.03–0.10% |
| Sector/thematic ETFs | 0.35–0.75% |
| Actively managed mutual funds | 0.5–1.2% |
| Old 401(k) share classes, annuity subaccounts | 1–2.5%+ |
| Adding a 1%-AUM advisor on top | +1% on everything above |
The empirical kicker: after fees, the majority of active funds underperform their index over 10–15 year periods (SPIVA data shows ~85–90% for US large-cap). Paying more doesn't buy more — expense ratio is the single best predictor of future relative fund performance, inversely.
Over 30 years at typical returns, a 1% fee consumes roughly a quarter of your final wealth versus a near-free index. 'One percent' is the most expensive-sounding-cheap phrase in finance.
The big one, but not alone: trading costs inside the fund, bid-ask spreads, sales loads (avoid entirely), 12b-1 fees, and account/advisor fees stack on top. The expense ratio is, usefully, the disclosed and comparable core.
It must beat its benchmark by its fee gap every year, persistently — which SPIVA data shows the large majority fail to do over a decade+. Genuine exceptions exist (some specialized strategies); the burden of proof sits on the expensive fund, and this calculator prices the burden.
On any fund page or your 401(k) fee disclosure. If your plan's cheapest S&P 500 option is above ~0.2%, that's worth a polite email to HR — plans have been sued over worse.
More, psychologically and mathematically: the fee is charged regardless of performance, so in a flat decade fees can consume most of the real return. Certain cost, uncertain reward.
At the cheap end they're equivalent (0.02–0.05%); ETFs add intraday trading and slightly better tax efficiency in taxable accounts. The fee decision is index-vs-active, not fund-structure.
Yes — every figure computes locally in your browser.
Check every fund you own against its cheap twin once — thirty minutes, this calculator, your fee disclosures. It's the highest guaranteed-return afternoon in personal finance, because unlike markets, fee savings never have a down year.