Why use this calculator
A 401(k) is the largest asset most American households will ever build outside their home, and almost all of the outcome is decided by three things you control: how early you start, what share of salary you defer, and whether you capture the full employer match.
This calculator projects all three forward, year by year, applying the actual elective deferral limit for your age so the projection cannot quietly assume you can save more than the law allows. It separates out what the employer match is worth by the end, which is usually a far larger number than people expect because the match compounds for the same decades your own money does.
It also restates the final balance in today's dollars, because a seven-figure number thirty years away is impossible to judge until it is converted into money you recognise. The figures are United States specific and use the 2026 limits published by the IRS.
How to use it
- Enter your age today and the age you expect to stop contributing, which sets the number of compounding years and decides when the catch-up limits begin to apply.
- Put in your current 401(k) balance from your latest plan statement, combining accounts if you have more than one.
- Enter your gross annual salary, since both your deferral and the match cap are calculated from it.
- Set your contribution as a percentage of salary, which is how the plan portal expresses it.
- For the match, enter the cents your employer adds per dollar you defer, so fifty for a half match and one hundred for dollar for dollar, then enter the share of salary they will match up to, which appears in your summary plan description.
- Finally set an expected return, a salary growth rate and an inflation assumption used only to restate the answer.
What each result means
- Years until retirement
- The number of compounding years in the projection, which is the single most powerful input on the page.
- This year's contribution limit
- The maximum you may defer at your current age under the 2026 rules, including any catch-up you qualify for.
- Your first-year contribution
- What your chosen percentage of salary actually puts in this year, after the legal limit is applied.
- First-year employer match
- What your employer adds in year one. Treat it as an immediate guaranteed return on the money you deferred.
- Balance at retirement
- The projected total at your retirement age, in future nominal dollars before any tax on withdrawal.
- Contribution for the full employer match
- The share of pay you need to defer to collect every dollar your employer offers to match. Contributing less than this leaves part of your pay package unclaimed, and the note shows roughly how much a year.
- Room left under this year's limit
- How much more you could defer into your 401(k) this year before reaching the elective deferral limit for your age, including any catch-up amount. Employer match does not count towards this limit.
- Balance without the employer match
- The same projection with the employer contributing nothing, which isolates how much of the result is yours alone.
- What the employer match is worth
- The difference between those two balances: the match plus every dollar of compound growth it produced.
- Your total contributions
- The sum of your own deferrals over the whole period, before any growth is counted.
- Total employer contributions
- The sum of all matching contributions, which is money you would simply not have received by opting out.
- Investment growth
- Everything in the final balance above what was actually paid in, which usually dominates over long periods.
- Balance in today's dollars
- The final balance restated at your inflation assumption, which is the only version you can meaningfully judge.
- Income at a 4% withdrawal rate
- A rough first-year income if you drew four percent, a common starting point for sustainable retirement drawdown.
The formula
For each year the model works out your deferral as salary multiplied by your contribution percentage, capped at the elective deferral limit for that age: $24,500 for 2026, plus an $8,000 catch-up from age 50 and a larger $11,250 catch-up for ages 60 to 63. The employer match is the lesser of your deferral and salary multiplied by the match limit percentage, multiplied by the match rate. The balance then becomes (previous balance + your deferral + match) multiplied by (1 + return rate), and salary grows by the salary growth rate before the next year. The result in today's dollars is the final balance divided by (1 + inflation) raised to the number of years.
How this number is used in practice
The employer match is the highest-return decision available to an ordinary worker. A fifty percent match on the first six percent of salary is an instant fifty percent return on those dollars before a single day of market growth, which no investment reliably offers. If your plan matches and you are deferring less than the match cap, you are turning down part of your own compensation.
On a $75,000 salary a half match on six percent is $2,250 a year, and across thirty-five years at seven percent that stream alone becomes well over three hundred thousand dollars. Check your summary plan description for the exact formula and the vesting schedule, because some plans only hand over the match after two to six years of service.
The second lesson is that time does more work than rate. Someone who contributes from twenty-five to thirty-five and then stops usually finishes ahead of someone who starts at thirty-five and contributes for thirty years, because the first ten years of compounding run for the longest.
If you are early in your career, a one or two percent rise in your deferral rate now is worth more than any fund selection you will make later. A practical approach is to raise the rate by one percentage point every time you get a raise, which most plans will automate for you.
Finally, judge the projection in today's dollars rather than the headline number. A balance of $1.85 million in 2061 sounds transformative, but at two and a half percent inflation it buys roughly what $780,000 buys now. Compare that figure against your current annual spending using a four percent withdrawal as a rough income test.
If the answer falls short, the fix is almost always a higher deferral rate or a later retirement age, not a more optimistic return assumption.
Worked examples
Age 30 to 65, $30,000 balance, $75,000 salary, 8% deferred, 50% match on the first 6%, 7% return
A projected balance of $1,852,167, of which $417,783 is attributable to the employer match alone.
The same worker deferring only 3%, below the match cap
The balance falls to $946,972 and the match is worth just $208,891, because only half of it is being claimed.
A late starter: age 50 to 67, $120,000 balance, $110,000 salary, 20% deferred with catch-ups, 100% match on 4%
A projected balance of $1,372,582, or $902,054 once restated in today's dollars.
When people use it
- Finding the minimum deferral rate that captures your full employer match
- Testing whether retiring two years earlier or later changes the outcome enough to matter
- Seeing what one extra percentage point of salary deferred is worth by retirement
- Judging a projected balance in today's dollars against your current annual spending
- Working out how much ground a late starter can make up using the age 50 and age 60 to 63 catch-ups
Tips
- Contribute at least up to the match cap before anything else. A 50% match is an immediate 50% return, and the 2026 deferral limit is $24,500.
- Raise your deferral rate by one percentage point with every pay rise. You never feel the cut because the raise covers it.
- Check the vesting schedule in your summary plan description. Unvested employer money is forfeited if you leave too early.
- From age 50 you can add a catch-up contribution, and ages 60 to 63 get a larger one still. Late starters should use both.
- A traditional deferral cuts your tax bill now; a Roth deferral is taxed now and comes out free later. Split the two if you cannot pick.
- Do not roll an old 401(k) into cash when you change jobs. Roll it into the new plan or an IRA so it keeps compounding.
- Fees matter enormously over decades. A one percent expense ratio instead of 0.1% can cost a fifth of the final balance.
What it assumes, and where it stops being accurate
- A constant annual return is applied every year. Real markets deliver an uneven sequence, and poor returns early in retirement hurt far more than the average suggests.
- The elective deferral limit is held at the 2026 figure for the whole projection. In practice the IRS indexes it upward most years, so long projections understate what you can save.
- No tax is applied to the final balance. Traditional 401(k) withdrawals are taxed as ordinary income, while qualified Roth withdrawals are not.
- Plan administration fees and fund expense ratios are excluded, and over decades they can consume a meaningful share of the result.
- Employer contributions are assumed to be fully vested. Many plans use a graded or cliff vesting schedule of two to six years.
- Social Security, pensions, IRAs, taxable brokerage accounts and home equity are all outside this projection.
Terms used on this page
- Elective deferral
- The amount you choose to have taken from your pay and put into the 401(k), subject to the annual IRS limit.
- Catch-up contribution
- An extra deferral allowed from age 50, with a larger amount available for ages 60 through 63.
- Vesting
- The process by which employer contributions become permanently yours, often over two to six years of service.
- Employer match
- Money your employer adds to your account in proportion to your own deferrals, up to a limit set by the plan.
- Four percent rule
- A planning rule of thumb that withdrawing four percent of a balance in the first year of retirement is broadly sustainable.
Questions people ask
- How much can I contribute to a 401(k) in 2026?
- The elective deferral limit is $24,500 for 2026. From age 50 you may add a catch-up contribution of $8,000, taking you to $32,500, and for ages 60 through 63 the catch-up is larger at $11,250, taking you to $35,750. These limits apply to your own deferrals only; employer matching contributions sit on top and are governed by a separate, much larger overall plan limit.
- What does an employer match actually mean?
- Your employer contributes alongside you according to a formula in the plan. A common one is fifty percent of what you defer on the first six percent of salary, so on $75,000 deferring six percent puts in $4,500 of yours and $2,250 of theirs. That is an immediate fifty percent return on those dollars, which is why capturing the full match should come before almost any other savings decision.
- What return rate should I assume?
- Seven percent is a widely used inflation-adjusted assumption for a diversified portfolio weighted towards equities, since the long-run US stock market return is roughly ten percent before inflation. Use seven percent with a low inflation figure if you want results in today's purchasing power, or ten percent with a full inflation assumption for nominal projections. Be more conservative as you approach retirement and shift towards bonds.
- Should I choose traditional or Roth contributions?
- Traditional deferrals reduce your taxable income now and are taxed as ordinary income when you withdraw. Roth deferrals give no deduction now but qualified withdrawals are entirely tax-free. Traditional generally suits high earners in peak earning years, Roth suits people early in their career or expecting higher rates later. Splitting between the two hedges the risk that future tax rates are not what you expect.
- Is the projected balance guaranteed?
- No. It assumes a steady annual return, and real markets deliver an uneven sequence of good and bad years. Two portfolios with identical average returns can end up far apart depending on when the bad years land, which matters most in the decade either side of retirement. Treat the projection as a planning guide, review it every few years, and adjust your deferral rate rather than your assumptions.
- What happens to my 401(k) when I change jobs?
- You can leave it with the old plan if the balance is large enough, roll it into your new employer's plan, or roll it into an individual retirement account. All three keep the money invested and tax-deferred. Cashing it out is the expensive option: you pay ordinary income tax plus, in most cases, a ten percent early withdrawal penalty before age fifty-nine and a half, and you lose all the future compounding.
Use this with
401(k) Retirement Calculator answers one part of the question. These pick up where it stops: Retirement Savings Calculator, Compound Interest Calculator, Paycheck Calculator and Australian Income Tax Calculator.
Where these figures come from
Figures and rules on this page follow United States federal rules.
- IRS: 401(k) limit increases to $24,500 for 2026. Elective deferral limit and the age 50 and age 60 to 63 catch-up amounts
- Internal Revenue Service. Federal income tax rules and forms for tax year 2026
- Investor.gov (U.S. Securities and Exchange Commission). Compound growth, fees and investor protection basics
401(k) Retirement Calculator produces an estimate for general information. It is not financial, tax, medical, legal or engineering advice. read the full disclaimer. Spotted a wrong number? Report it and it gets fixed. The form picks up this calculator and the inputs you used.