Short answer: investing the same amount every month is called dollar-cost averaging — but this calculator answers the question that matters more: what do fund fees quietly take from that habit over time? Example: $300 a month for 15 years at an assumed 8% return grows to $104,224 in a 0.03%-fee index fund and $99,955 in a 0.50%-fee fund — a $4,269 difference from fees alone, on $54,000 invested.
| End value in Fund A (lower fee) | — |
| End value in Fund B (higher fee) | — |
| Total you invested | — |
| Growth in Fund A | — |
See the full breakdown
IMPORTANT — this is a fee-comparison scenario, not a prediction. It assumes a smooth return you choose, identical for both funds, with each fund’s annual fee subtracted from that return. Real markets zigzag, real funds earn different returns, and dollar-cost averaging does not remove market risk. The honest takeaway is only about fees: given the same gross path, the cheaper fund keeps more.
How this calculator works — and its honest limits
Each month your deposit goes in, then the balance grows at (assumed return − fund fee) ÷ 12. Two identical paths, two fee levels: the entire gap between the lines is fee drag, compounding. What this model deliberately does NOT do: predict returns, simulate market crashes, or claim DCA beats lump-sum investing (on average, historically, investing money as soon as you have it has won more often, because markets rise more than they fall). DCA’s real product is behavioral — it keeps you investing through scary headlines. The fee gap, by contrast, is arithmetic, not opinion.
Worked example
- $300/mo, 15 years, assumed 8% → Fund A (0.03% fee): $104,224; Fund B (0.50% fee): $99,955; drag $4,269 on $54,000 contributed.
- Zero-return stress test (assumed 0%): Fund A ends at $53,878, Fund B at $52,013 — with no growth at all, fees visibly eat principal.
- Small/short check: $100/mo, 5 years, assumed 6% → 0% fee: $7,012 vs 1% fee: $6,829.
FAQs
Is dollar-cost averaging a good strategy? It’s a good habit — automatic, emotion-proof. As a return-maximizing trick, the evidence is mixed at best; this page won’t pretend otherwise. Where do I find a fund’s fee? It’s the “expense ratio,” on every fund’s page and prospectus. Index funds commonly charge 0.03–0.20%; actively managed funds often 0.50–1%+. Does a higher fee ever pay for itself? Only if the fund out-earns the cheaper one by more than the gap, after the fee, for years. That’s the claim any pricey fund has to prove — the chart shows the size of the head start it needs.
Sources: Investor.gov: dollar cost averaging, Investor.gov: expense ratio Figures last verified Report a wrong number