See how your retirement savings grow over time, what that's worth in today's dollars after inflation, and roughly how much monthly income it could support.
Your numbers Free
Projected Balance at Retirement
$0
Worth $0 in today's dollars after inflation
$0
You'll contribute
$0
Investment growth
$0
Est. monthly income (4% rule)
Growth over time
Age
Years from now
Balance (nominal)
Balance (today's $)
"Today's dollars" shows what each future balance would actually buy at today's prices, after accounting for the inflation rate above.
Quick answers
What is the 4% rule?
A common (though debated) retirement planning guideline: if you withdraw about 4% of your portfolio in your first year of retirement, then adjust that dollar amount for inflation each year after, your savings have historically had a good chance of lasting 30 years. It's a starting estimate, not a guarantee — market conditions, sequence of returns, and how long you live all affect whether it actually holds up.
Is 7% a realistic annual return to assume?
7% is a commonly used estimate for long-term diversified stock market returns after adjusting for inflation is sometimes baked in differently depending on the source — some use 10% nominal (before inflation) and 7% real (after inflation). This calculator treats your input as a nominal return and separately adjusts for inflation at the end, so make sure you're not double-counting inflation in your return assumption.
Does this account for employer 401(k) matching?
Not automatically — if your employer matches contributions, add that match amount into your "monthly contribution" field to include it in the projection. Free employer match money is one of the highest-return moves in personal finance; always try to contribute at least enough to get the full match.
How to use this calculator
It projects a balance forward and then applies the 4% withdrawal rule to it. Both halves are assumptions you control, so the numbers are only as good as the inputs.
Enter your current age and the age you plan to stop working. The gap is how long contributions compound.
Enter what is already invested, then the monthly contribution including any employer match. Leaving the match out is the most common way this projection comes in low.
Set an expected annual return. A long-run average is an average, not a sequence, and the page applies it evenly to every year.
Set expected inflation, which drives the "today's dollars" line and is the number to read if you are asking what the money will buy.
Compare the nominal income against the inflation-adjusted income. They are different sentences about the same balance.
A worked example: starting at 35, retiring at 65
$20,000 invested today, $500 a month, 7% a year, 3% inflation, thirty years of contributions. The projected balance is about $772,000.
In today's dollars that is about $318,000, because thirty years of 3% inflation cuts the buying power of a nominal dollar by more than half.
Apply the 4% rule and the two numbers separate further. Four percent of the nominal balance is about $2,574 a month. Four percent of the inflation-adjusted balance is about $1,061 a month in today's buying power. The first figure looks like a comfortable retirement and the second is a tight one, and they come from the same projection.
Of the $772,000, about $200,000 is your own money — the $20,000 plus 360 deposits of $500. The remaining $572,000 is growth. That is the argument for starting early, and also the reason the result is so sensitive to the return you type.
What your results mean
The 4% rule is a planning convention from historical return studies, not a guarantee and not a withdrawal strategy. It says that withdrawing 4% of the starting balance, adjusted for inflation, survived most historical thirty-year periods. It says nothing about the next thirty.
Constant returns are the biggest simplification. Real markets deliver the same average through very different paths, and a bad first decade in retirement does damage that a later recovery cannot fully undo. The page does not simulate a sequence of returns.
Not included: Social Security, pensions, an annuity, taxes on withdrawals, and investment fees. A 1% fee is a full percentage point off the return you typed, which over thirty years is a large fraction of the growth line.
The contribution rate moves the result more than the return assumption does, and it is the one input you can still change. Raising the monthly amount is a decision; raising the assumed return is a wish.
Frequently asked questions
What return should I assume?
Something defensible for your mix, net of fees, and then run a lower one as a stress test. A projection that only works at the optimistic end is not a plan. The page applies your rate evenly, which flatters any volatile portfolio.
Why does the "today's dollars" figure matter?
Because you will spend tomorrow's dollars on tomorrow's prices. A nominal balance answers "how many dollars", while the inflation-adjusted figure answers "how much life". The second is the one that tells you whether the plan works.
Does the 4% rule still hold?
It is a widely used starting point, and some researchers argue for a lower rate when valuations are high or fees are not accounted for. Treat 4% as a conservative default, not a rule of nature, and test 3% as well.
Should the employer match be in my contribution?
Yes, if it is vested or you expect it to be. It is money going into the same account, so leaving it out understates the projection by a meaningful amount.
What about Social Security?
It is not modeled. If you expect a benefit, it reduces how much this balance has to cover, which is a material part of most retirements. Get your estimate from the Social Security statement rather than a guess.
Is the inflation adjustment applied to contributions?
The projection compounds contributions at the nominal return and deflates the final balance. It does not raise your contribution over time, so if you plan to increase it with raises, the real result would be higher.
Sources & references
The future-value math is standard. The 4% rule is a research convention, and the page labels it as one.