When Will I Be a Millionaire? Calculator
Enter what you've invested, what you add monthly, and an expected return. You'll get the year you cross $1 million (or your own target), how much of it you contributed versus growth, and what doubling your monthly would do.
Invested assets only: brokerage, retirement accounts, cash you'll invest
After inflation. 5% is a common long-run stock assumption
Leave empty for the classic $1,000,000
You cross $1M in
—
Enter what you have and what you invest monthly
Total you'll have contributed
—
At double the monthly
—
Enter a monthly amount
Years to $1M at different monthly amounts
| Invested per month | Years to $1M |
|---|---|
| $250 | 58 |
| $500 | 45 |
| $1,000 | 33 |
| $2,000 | 23 |
| $3,000 | 18 |
| $5,000 | 13 |
Starting from $0 at a 5% after-inflation return, so the target reads in today's purchasing power.
The boring path is the reliable one
Most millionaires aren't made by a lucky stock pick. They're made by a steady monthly amount going into broad index funds for a couple of decades, which is exactly the machine this calculator simulates. No timing, no hot tips, just contributions and compounding taking turns doing the work. If the investing side is new to you, our start-investing guide walks through the whole setup, and the compound interest explainer covers why the math works at all.
Why the first $100k is the hardest
Run the numbers and you'll notice the timeline is front-loaded with effort. Early on, nearly every dollar of progress is a dollar you contributed, because a small balance earns small returns. But once the portfolio is large, growth starts matching and then dwarfing your contributions: the last $100,000 often arrives in a tenth of the time the first one took. That's the curve behind the "total contributed" stat above, and it's why the compound interest calculator shows growth bending upward instead of climbing in a straight line. The slow start isn't a sign the plan is failing. It's the plan.
A milestone, not a finish line
Crossing $1 million is a net worth milestone, and net worth is the number that actually describes financial health: income tells you what flows in, net worth tells you what stayed. Whether a million is "enough" depends entirely on your spending, which is what the FIRE calculator turns into a personal target. Start by measuring where you stand with the net worth calculator, and if you'd rather see that number update itself every month instead of rebuilding a spreadsheet, Stoia tracks net worth across all your accounts automatically.
Frequently asked questions
How long does it take to become a millionaire?
It depends almost entirely on how much you invest monthly and your return. From a standing start, roughly $1,500 a month at a 5% after-inflation return crosses $1 million in about 27 years. Double the monthly and it drops near 19 years. A head start of $100,000 cuts years off either path.
Does $1 million still mean what it used to?
Not in raw dollars, which is exactly why this calculator asks for an after-inflation return. Using a real return means the $1 million you cross has today's purchasing power, not a diluted future version. If you want a bigger cushion, set a custom target like $1.5 or $2 million.
Should I count my house toward the million?
For this calculator, most people shouldn't. The math here assumes assets that compound and can eventually be spent: brokerage accounts, 401(k)s, IRAs. Home equity counts toward total net worth, but it doesn't pay bills unless you sell or borrow against it, so it muddies the timeline.
What return should I assume?
U.S. stocks have returned roughly 9 to 10 percent a year over long periods before inflation, which works out to about 5 to 7 percent after it. Using 5% keeps the estimate conservative; if reality does better, you arrive early, which is the good kind of surprise.
Is saving more really better than chasing higher returns?
In the first decade, yes, and it isn't close. Doubling your monthly contribution reliably moves the date by years, while squeezing an extra percent of return barely moves it until the balance is large. Contributions are also the only lever you fully control.
Does this calculator save my numbers?
No. Everything runs in your browser and disappears when you leave. Nothing is uploaded or stored.
Want this to update itself?
Stoia connects your real accounts and keeps the full picture current: net worth, budgets, and goals. Launching in 2026.