Investment Fee Calculator (Expense Ratio Drag)
Enter your balance, contributions, timeline, and your fund's expense ratio. You'll see your projected balance, the dollars lost versus a 0.03% index fund, and the same plan at four fee levels.
Long-run stock averages are often quoted near 7-10%
On the fund's fact sheet; many broad index funds charge under 0.1%
Balance after 30 years
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Enter a balance or contribution
Lost to fees vs a 0.03% index fund
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Fee drag
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Compounding works on costs too
The engine that turns steady contributions into wealth, growth earning growth, runs just as faithfully for whoever collects the fee. A 1% expense ratio doesn't take 1% of your final wealth; it takes 1% of your balance every year, including all the years when the balance is large, and it takes the decades of growth that money would have produced. Run a typical 30-year plan above and the drag lands near a quarter of the ending balance. Nobody would sign up for "we keep a fourth of your retirement," but that is the same contract written in smaller print.
Where fees hide
Expense ratios are only the most visible layer. Advisory fees charged as a percent of assets sit on top and follow identical math: 1% for advice plus 0.6% in fund fees is a 1.6% drag, which the calculator can model as a single number. Below both sit quieter costs: trading spreads, sales loads on some funds, and cash sitting idle. None of these show up as a bill, which is precisely the problem. The habit that fixes it is boring: once a year, look up the expense ratio of everything you own and add the layers together. The compound interest calculator shows what the recovered drag earns if you redirect it.
What low-cost index funds changed
The index fund's real innovation wasn't matching the market, it was doing so at a price rounding to zero, which turned fees from an accepted cost of investing into a choice. Today a diversified portfolio can cost 0.03-0.10% a year, and our guide to getting started walks through building one in an afternoon. The remaining work is simply noticing: fees hide best in accounts nobody looks at, the old 401(k) from two jobs ago being the classic offender. Keeping every account visible in one place, the way Stoia's net worth tracking does, is how the forgotten ones get found.
Frequently asked questions
What is an expense ratio?
The annual fee a fund charges, expressed as a percent of your money in it. A 0.50% expense ratio costs $50 a year per $10,000 invested. It is deducted from the fund's assets a little each day, so you never see a bill, only slightly lower returns.
How can a 1% fee cost hundreds of thousands of dollars?
Because the fee removes money that would have compounded for decades. Each year's fee is small, but the growth that money would have produced, and the growth on that growth, is not. Over a 30-40 year investing life, a 1% annual fee typically consumes roughly a quarter of the final balance compared to a near-free index fund.
What counts as a low expense ratio?
Broad stock and bond index funds now commonly charge 0.02% to 0.10%. Actively managed funds often charge 0.5% to 1% or more. There's no hard line, but every extra tenth of a percent needs to earn its keep, and the math in this calculator shows how big that ask really is.
Do I ever see the fee leave my account?
No, and that's why fees survive. The fund's share price is reported after fees are taken out, so there is no line item, no receipt, and no moment of decision. The only way to see the cost is to compute the alternative, which is what this tool does.
Are advisor fees on top of fund fees?
Yes. An advisor charging 1% of assets per year stacks on top of the expense ratios of the funds they put you in, and both drag the same compounding. The math on this page applies to the combined number, so it's worth adding them up before entering a figure.
Does this calculator save my numbers?
No. Everything runs in your browser and disappears when you leave. Nothing is uploaded or stored.
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