Model how your portfolio grows with regular contributions, then see the three things most investment calculators hide from you: what fund fees quietly cost, what that future number is really worth in today's money, and how many years it lasts once you start withdrawing.
Educational tool, not financial advice. SavingsClub is not a licensed financial advisor. Projections are estimates and investment returns are never guaranteed.
A 7 to 8 percent return is a common long-run planning assumption for a stock-heavy portfolio. The S&P 500 has averaged roughly 10 percent before inflation, closer to 7 percent after it.
Enter your starting amount, monthly contribution, expected return, and time horizon, then click Calculate.
The investment future value calculator above runs the same loop your portfolio does in real life. Each month it grows your balance by the monthly rate of return, then adds your contribution, and repeats. Do that for every month of your time horizon and you have your future value.
Written out, the monthly rate is your annual return divided by twelve. So an 8 percent expected return becomes about 0.667 percent per month. Start with your initial balance, multiply by one plus that rate, add your monthly contribution, and carry the result into the next month. After 360 iterations you have a 30-year projection.
The reason this compounds so hard is that your contributions start earning returns of their own. On 10,000 dollars plus 500 dollars a month at 8 percent for 30 years, you would personally put in 190,000 dollars. The projected balance is roughly 843,947 dollars. The difference, about 653,947 dollars, is money the market made on money the market had already made.
An expense ratio of 1 percent sounds like nothing. It is presented as nothing. It is not nothing, because it is charged every single year against a balance that is growing, so the fee compounds against you exactly the way your returns compound for you.
Take that same portfolio: 10,000 dollars, 500 dollars a month, 8 percent, 30 years.
| Expense ratio | Final balance | Lost to fees |
|---|---|---|
| 0.058% (average index mutual fund) | $843,947 | Baseline |
| 0.57% (average active mutual fund) | $756,625 | $87,322 |
| 1.00% | $691,150 | $152,797 |
A 1 percent fee costs about 152,797 dollars, which is roughly 18 percent of the final balance. You did the saving. You took the market risk. Nearly a fifth of the result went somewhere else. Move the fee slider in the calculator above and watch it happen to your own numbers.
The figures are not invented. According to Morningstar data through the end of 2025, passive index mutual funds averaged an expense ratio of 0.058 percent and passive ETFs averaged 0.135 percent, while actively managed mutual funds averaged 0.57 percent. If an index fund you own charges more than about 0.20 percent, you are paying above the going rate for identical exposure.
Mostly they do not. Morningstar's Active/Passive Barometer found that 38 percent of active funds beat their comparable passive peers in 2025, down from 42 percent the year before. Over the ten years through 2025, only about 21 percent of active funds both survived and outperformed. That is the entire case for keeping costs low: you are not betting against a manager's skill, you are declining to pay a guaranteed cost for an unlikely benefit.
This is where most investment calculators quietly mislead people. They show you 843,947 dollars in thirty years and let you feel wealthy. But a dollar in 2056 does not buy what a dollar buys today.
At 3 percent inflation, that 843,947 dollar portfolio has the purchasing power of about 347,695 dollars in today's money. In other words, roughly 59 percent of the headline number is inflation rather than wealth. That is not a flaw in the projection, it is the truth about long-horizon numbers, and it is why the calculator above shows both figures side by side. Our inflation calculator goes deeper on this if you want to see it in isolation.
Knowing the real figure changes decisions. If your goal is a 500,000 dollar retirement in today's money, targeting a 500,000 dollar nominal balance in thirty years will leave you dramatically short.
Almost every free investment calculator stops at the finish line. It hands you a big number and walks away. But the number is not the goal, the income it produces is the goal, and that is a completely different calculation. The investment drawdown calculator built into this page continues past retirement day and asks the only question that really matters: how many years does this last?
The mechanics are straightforward. Each year your remaining balance earns a return, and each year you withdraw an amount, adjusted for inflation. If your withdrawal is smaller than your growth, the balance can last indefinitely. If it is larger, the money runs down, and the speed accelerates as the balance shrinks.
The famous 4 percent rule came from William Bengen's 1994 research, and it has been treated as gospel ever since. The honest picture in 2026 is more nuanced. Morningstar's latest research puts the safe starting withdrawal rate for a 30-year retirement at 3.9 percent for someone taking a fixed, inflation-adjusted income. Bengen himself has since revised his own worst-case safe maximum upward to 4.7 percent. And Morningstar found that retirees willing to flex their spending when markets fall can often sustain considerably more.
The gap between those numbers is the point. There is no single correct withdrawal rate, because the answer depends on how rigid you are willing to be. A retiree who cuts spending in a bad year can safely start higher than one who cannot. Model a few rates in the drawdown tool above rather than trusting any single rule.
An 8 percent average return does not mean 8 percent every year. It means some years are up 25 percent and others are down 20 percent, and the order they arrive in matters enormously.
While you are still contributing, a crash early on is genuinely good news. Your monthly contributions buy more shares at lower prices, and you are rewarded when the market recovers. This is why young investors should hope for a bad decade, not fear one.
Once you are withdrawing, the same crash is dangerous. You are selling assets at depressed prices to fund your living costs, which permanently removes shares that would have participated in the recovery. Two retirees with identical average returns can end up in completely different places based purely on whether the bad years arrived first or last. This is why the drawdown estimate above should be treated as a planning guide, not a promise, and why holding some cash or bonds near retirement matters more than it does at 30.
Investing is the third step, not the first. Two things come before it.
An emergency fund. If a car repair forces you to sell investments in a down market, your portfolio has become your emergency fund, and that is exactly the wrong job for it. Size yours with the emergency fund calculator.
High-interest debt. Paying off a credit card charging 22 percent is a guaranteed 22 percent return. No investment offers that with certainty. Clear it first, and use the credit card payoff calculator to see what the balance is really costing you.
After that, the order most people follow is: capture any employer 401(k) match, since that is an instant return you cannot get anywhere else, then fund tax-advantaged accounts, then invest in a taxable brokerage. Our 401(k) calculator and Roth IRA calculator handle the first two, and the compound interest calculator shows the underlying engine in its simplest form.
The S&P 500 has historically returned about 10 percent per year before inflation, which is roughly 7 percent after inflation. Using 7 to 8 percent for a long-term projection is a reasonable planning assumption. Past performance never guarantees future results, so treat any single number as an estimate rather than a promise.
Take your starting balance, apply the monthly rate of return, then add your monthly contribution, and repeat for every month of the term. In formula terms, future value equals the starting balance grown at the periodic rate plus the future value of the stream of contributions. The calculator on this page runs that month by month so you do not have to.
Far more than the percentage suggests, because the fee is charged every year on a growing balance. On 10,000 dollars plus 500 dollars a month at an 8 percent return over 30 years, a 1 percent expense ratio costs about 152,797 dollars, which is roughly 18 percent of the final balance. The same money in a fund charging 0.058 percent keeps almost all of that.
According to Morningstar data through the end of 2025, passive index mutual funds averaged 0.058 percent and passive ETFs averaged 0.135 percent, while actively managed mutual funds averaged 0.57 percent. If an index fund charges more than about 0.20 percent, you are paying above the going rate for the same exposure.
Because inflation reduces what each dollar buys. At 3 percent inflation, a portfolio projected to reach 843,947 dollars in 30 years has the purchasing power of about 347,695 dollars today. That is not a flaw in the math, it is the reality that large future numbers are partly an illusion, which is why this calculator shows both figures.
It depends on your withdrawal rate and the returns you earn while withdrawing. The drawdown tool on this page models it year by year. As a reference point, Morningstar research put the safe starting withdrawal rate for a 30-year retirement at 3.9 percent in 2026, while William Bengen, who created the original 4 percent rule, has since revised his worst-case safe maximum up to 4.7 percent.
It is a useful starting point rather than a plan. It assumes a fixed inflation-adjusted withdrawal over 30 years and does not account for your taxes, your other income, or your actual spending pattern. Retirees willing to adjust spending when markets fall can often sustain a higher rate, while a rigid withdrawal in a bad early market is what tends to break plans.
Usually not, once fees are counted. Morningstar found that 38 percent of active funds beat their passive peers in 2025, and over the 10 years through 2025 only about 21 percent of active funds both survived and outperformed. That is the main argument for keeping costs low rather than trying to pick a winning manager.
It is the risk that the order of your returns hurts you, not just the average. An average of 8 percent does not mean 8 percent every year. While you are still contributing, a bad early market is actually helpful because you buy cheaply. Once you are withdrawing, a bad early market is dangerous, because you sell assets at low prices and the portfolio may never recover.
Enough that it continues through a bad month, which usually means a figure you can automate and forget. Consistency matters more than the amount early on. Use the calculator above to see how a small increase compounds, then check that the money is not needed for an emergency fund or high-interest debt first, because both should generally come before investing.