How this calculator works
The projection compounds your balance month by month. Each month the running balance earns a net return — your expected annual return minus the fund’s expense ratio, divided by twelve — and then your monthly contribution is added on top. Repeating this for every month of the period produces the ending balance.
To show the cost of fees, the same path is run a second time with no expense ratio. The gap between that fee-free balance and your actual net balance is what the expense ratio quietly took out of your returns over the period.
Reading the results
The ending balance is what your account is projected to hold at the end of the period after fees. Total contributions is simply the money you put in: the initial investment plus every monthly deposit.
The growth and fees charts split the story apart. Investment growth is the ending balance minus everything you contributed, while fees paid is the earnings the expense ratio cost you. The line chart traces the net balance climbing year by year so you can see how compounding accelerates over time.
Practical tips
A few habits make a large difference over a multi-decade horizon:
- Favor low-cost funds. An expense ratio difference of even half a percent compounds into a meaningful sum over decades.
- Contribute consistently. Regular monthly deposits smooth out market timing and add the most fuel to compounding.
- Start early. The first dollars invested have the longest time to grow, so they do the heaviest lifting.
Caveats
Real fund returns are not a smooth fixed rate; markets rise and fall, and the order of those swings affects outcomes. This model also ignores taxes, sales loads, and inflation, so a future balance buys less than the same number does today.
Treat the figures as an educational estimate, not financial advice or a guarantee of returns. Consider speaking with a qualified financial professional before making investment decisions.
Formula
net monthly rate = (annualReturn − expenseRatio)/100/12; balance compounds monthly with contributionsFrequently asked questions
- Why do small expense ratios matter?
- Even a 0.5% fee compounds over decades. The fees figure here shows the lost growth versus a fund with no expense ratio.