401(k) Calculator

Project your 401(k) to retirement with catch-up contributions and fee drag actually modelled, and the answer given in what it buys now.

The smaller number is the honest one

Every 401(k) calculator hands you a large figure and lets you feel good about it. The projection above hands you two, and the smaller one is the honest one.

A million dollars thirty years from now isn't a million dollars. At 3% inflation it buys roughly what $412,000 buys today. That's still a serious sum. But it starts a different conversation from the one the big number starts, and it's the figure you should actually plan around. Both are shown above for exactly that reason.

Three things this models that most calculators skip

The catch-up limit steps up, and then it steps back down

From the year you turn 50 the §402(g) limit rises. Between 60 and 63 it rises again, and at 64 it drops back to the ordinary catch-up. Nearly every free calculator explains those rules somewhere on the page and then ignores them in the arithmetic, projecting one flat limit across your whole career. This one steps the cap with age. If you're planning to save hard in your fifties, that's the difference between a projection you can use and one you can't.

A 1% fee is not a 1% cost

A 1% expense ratio compounds against you every year for the whole period, and the damage never appears on a statement. Set the fee field to your plan's real expense ratio (it's in the annual fee disclosure, usually a few pages in) and the calculator gives you the cost in dollars. Over a full career it's routinely a six-figure number. Of the calculators ranking for this search, only one has a fee field at all. I checked eight. Maybe I missed one.

Real match formulas have two tiers, and sometimes a dollar cap

Plan formulas are rarely a single rate. "100% on the first 3%, then 50% on the next 2%" is common, and some plans cap the match at a flat dollar figure instead of a percentage of salary. Both work above. If what you want is the exact contribution rate that collects every matched dollar, the employer match calculator solves for it directly, and it also shows what you'd keep of the match if you left the job today.

How do you calculate 401(k) growth by hand?

Grow last year's 401(k) balance by your return after fees, add the year's contributions with half a year of growth on them, and run that same line once for every year until you retire.

1. Take the return you expect and subtract the plan's fee. A 7% gross return with a 0.5% expense ratio compounds at 6.5%, and the net figure is the only one that counts.
2. Add up one year of contributions. On $85,000 at 10% that's $8,500 of your own money, plus $3,400 of match from a formula paying 100% on the first 3% and 50% on the next 2%, so $11,900 goes in.
3. Grow the opening balance for a full year. $50,000 at 6.5% becomes $53,250.
4. Grow the year's contributions for half a year, because payroll delivers them across twelve months and not on 1 January. $11,900 at 3.25% is $12,286.75.
5. Add the two. Year one closes at $65,536.75, and that becomes the opening balance for year two.
6. Repeat, lifting the salary by your pay-rise assumption each year and stepping the §402(g) cap up at 50 and again at 60. Thirty repetitions of one line is the whole projection above.

Two things go wrong when people rebuild this in a spreadsheet. The first is the fee: an expense ratio comes off the return before anything compounds, so 7% less 0.5% is 6.5%, and taking the fee off the final balance instead understates the damage badly. The second is the timing convention. A spreadsheet's FV function assumes every contribution lands either at the start or at the end of the period, neither of which is what payroll does, and that alone is why the same inputs give different answers in different tools. And the result is in future dollars: divide by 1.03 for every year that passes to see it in today's buying power, which is the second figure printed above.

What a single fixed return rate hides

Every deterministic calculator, this one included, assumes your money earns the same percentage every year. Markets don't. The gap matters.

Two portfolios can average identical returns over thirty years and finish in very different places depending on when the bad years land. Losses early in retirement, while you're drawing the money down, do far more damage than the same losses late. That's sequence-of-returns risk. No fixed-rate calculator can show it to you, this one included.

So treat the figure above as a sketch of one plausible path. It's good for comparing choices, contributing 8% against 12% or retiring at 62 against 67, because the comparison holds even when the absolute figure doesn't. The 7% default is a nominal return with 3% inflation handled separately; if you hold a lot of bonds, lower it.

Frequently asked questions

How much will my 401(k) be worth at retirement?

Your balance at retirement depends on four things: what you put in, what your employer adds, how long it compounds, and what it earns after fees. The calculator above runs it year by year with the IRS limits enforced along the way, and shows the result in both future dollars and today's.

What rate of return should I use?

Most calculators default to 7%. This one handles inflation separately, so a nominal 7% with 3% inflation is a fair middle assumption for a stock-heavy portfolio. Lower it if you hold bonds. Nobody knows the real figure in advance.

Do employer contributions count toward the $24,500 limit?

No. The §402(g) limit covers only your own deferrals. Employer money counts toward the separate §415(c) combined limit of $72,000, and this calculator enforces both, so it'll never project a contribution the law doesn't allow.

How much do 401(k) fees really cost?

More than almost anyone expects. The fee compounds against you for the whole period. Set the fee field to your plan's expense ratio and the calculator shows the difference in dollars. At 1% a year over a career, expect a six-figure gap.

What are catch-up contributions?

Extra deferrals the IRS permits from the year you turn 50, which take the limit to $32,500. Between 60 and 63 an enlarged catch-up takes it to $35,750, and at 64 it reverts to the ordinary catch-up.

Each of the other calculators answers a question this one can't

Every tool below reads its IRS figures from the same verified data file as the projection above, and each one says what it leaves out. Pick by the question you're actually asking.

Read the fee page first, whatever else you skip

If none of this is familiar yet, start with how a 401(k) works and read it in order, because every figure on this page quietly assumes you already know what the match is and why the money stays put until 59½. It's the page I'd hand a new hire.

After that, three pages move the figure above more than the others do: whether you're behind for your age, what your plan's expense ratio is quietly removing from it (at 1% a year that's about a fifth of the final balance) and what you'd keep if you took the money out early. Do the fee one first. It's the only one you can act on this week with a form.

Inside the account you make two choices, and only one of them has a deadline. Whether your money goes in pre-tax or Roth can be switched in any pay period you like. What happens to an old balance when you leave the job gets settled in the fortnight after you resign, usually by whichever box on the exit paperwork takes least effort, and that fortnight is where most 401(k) money is permanently lost.

The rest are for particular situations, so read one only if it's yours. A 403(b) at a school or hospital. A solo 401(k) if you work for yourself. A 457(b), whose limit doesn't share with the 403(b) sitting next to it, so public-sector staff offered both can defer $24,500 twice. Borrowing against the balance, or pacing the year so December lands on the cap, or what the pot pays a month once you stop. And the IRA, which is where money above the match usually belongs if your plan's funds are dear.

Three things are true here that aren't true of most free calculators

Each one exists because a competing calculator got it wrong.

• One source of truth for every figure. No IRS number is typed into a page; they all come from a single data file with its citation attached, so an update is one change instead of forty. Stale limits are the most common failure in this category. At the time of writing, several well-ranked calculators are serving figures a year out of date, and one cites an IRS notice that doesn't exist.
• The build refuses to publish an unverified number. If a figure hasn't been checked against the primary source, the tool switches itself off and says so, instead of showing a plausible estimate.
• Every calculator states what it doesn't model. A deterministic projection sketches one path out of thousands and can't forecast any of them, so each tool here says where it simplified.

The methodology page sets out the formulas. I also checked how accurate 401(k) calculators actually are: half of the eight I could check were publishing at least one wrong 2026 figure, and the same check applies to this site.