Expense Ratio Impact Calculator
See how much a fund's expense ratio costs you over time by comparing the gross and net growth of your investment and the total dollars lost to fees.
How to use this tool
- Enter the lump sum you plan to invest.
- Enter the fund's gross annual return before fees.
- Enter the expense ratio (e.g. 0.5%).
- Enter how many years the money stays invested.
- Compare the fee-free value with the after-fee value and the total fees lost.
A fund's expense ratio looks small but compounds against you for decades. Enter your investment, return, fee, and horizon to see the gross value, the after-fee value, and the total dollars lost to fees.
Formula
Value with no fees = Principal × (1 + gross return)n.
Value after fees = Principal × (1 + gross return − expense ratio)n, modelling the expense ratio as an annual drag on the return.
Total lost to fees = Value with no fees − Value after fees. Because the drag compounds, the lost amount grows far faster than the headline fee suggests.
How it works
An expense ratio is the annual percentage a fund charges to cover its operating costs. It is deducted from the fund's assets every year, so it behaves like a constant subtraction from your return. A 0.5% ratio sounds trivial, but over decades the gap between a fee-free and a fee-paying portfolio compounds into a large, often surprising, sum.
This calculator models the expense ratio as a flat reduction in the annual growth rate and compares two otherwise identical investments — one growing at the gross return and one at the gross return minus the expense ratio. The difference at the end is the total dollars the fee cost you, including the growth those fees would themselves have earned. This is why low-cost index funds are so heavily favoured for long-term investing.
The model assumes a single lump sum, a constant return, no additional contributions, and no taxes or trading costs; it also treats the expense ratio as a simple subtraction from the return, which closely approximates how fees accrue on a steadily growing balance. Reviewed by the AbraCalc Investing Desk. This tool provides general information, not investment advice; verify figures and consult a licensed professional before investing.
Worked example
$100,000 invested, 7% gross return, 0.5% expense ratio, 30 years
- Value with no fees = $100,000 × (1.07)30 = $761,225.50.
- Net return = 7% − 0.5% = 6.5%.
- Value after fees = $100,000 × (1.065)30 = $661,436.62.
- Total lost to fees = $761,225.50 − $661,436.62 = $99,788.89.
Value with no fees: $761,225.50 — after fees $661,436.62, total lost to fees $99,788.89.
Total lost to fees on $100,000 over 30 years (7% gross return)
| Expense ratio | Roughly equivalent to | Total lost to fees |
|---|---|---|
| 0.03% | Ultra-low-cost index fund | $6,376.87 |
| 0.20% | Low-cost index fund | $41,548.57 |
| 0.50% | Moderate-cost fund | $99,788.89 |
| 1.00% | Typical active fund | $186,876.39 |
| 1.50% | High-cost active fund | $262,830.38 |
Key terms
- Expense ratio
- The annual fee a fund charges as a percentage of the assets you hold in it, deducted automatically.
- Fee drag
- The cumulative reduction in returns caused by ongoing fees compounding over time.
- Gross return
- A fund's return before its expense ratio and other costs are subtracted.
- Net return
- The return you actually keep after the expense ratio is deducted.
- Basis point
- One hundredth of a percent (0.01%); fund fees are often quoted in basis points.
Frequently asked questions
- What is an expense ratio?
- It is the annual fee a mutual fund or ETF charges, expressed as a percentage of your invested assets. A 0.5% ratio means you pay $5 per year for every $1,000 invested.
- Why do small fees matter so much?
- Fees compound. Each year's fee reduces the balance that could have grown in future years, so over decades a fraction of a percent can erase six figures of wealth on a large portfolio.
- How is the fee impact modelled here?
- The calculator subtracts the expense ratio from the gross return and compounds both rates separately, then reports the difference as the total lost to fees.
- What expense ratio should I look for?
- Broad-market index funds often charge well under 0.10%, while actively managed funds can charge 0.5–1.5% or more. Lower-cost funds keep more of the return in your pocket.