401(k) Calculator guide
Project your 401(k) balance at retirement with employer matching, yearly raises, the 2026 IRS contribution limit, and catch-up contributions after 50, so you can see exactly how much free match money you might be leaving on the table.
How the projection works
Each simulated year, the calculator takes your salary, applies your contribution percentage, caps it at the IRS limit (plus catch-up if you are old enough and the box is checked), then adds the employer match. The match is the match rate times whichever is smaller: your contribution or the match cap as a percent of pay. The existing balance grows by your return assumption, the year's contributions are added at year end, and your salary rises by the raise percentage before the next year starts.
Year-end contributions are a slight simplification. Real payroll deposits happen every paycheck, so they earn a little growth during the year. The difference is small, a few percent of the final balance, and it errs on the conservative side.
Worked example: the default scenario
Age 30, retiring at 65, $25,000 already saved, $75,000 salary, 8% contribution, employer matches 50% up to 6% of pay, 3% raises, 7% return. Over 35 years you contribute about $362,800 and your employer adds about $136,000. The projected balance at 65 is roughly $1.89 million. Around $1.36 million of that is investment growth, which is the point: in a long career, growth dwarfs contributions.
That $1.89 million is in future dollars. At 3% inflation, prices roughly 2.8 times higher in 35 years means it buys what about $671,000 buys today. Still a strong outcome, but a very different number to plan around. Run the inflation calculator on your result before deciding it is enough.
The match is the best return you will ever get
Drop the contribution from 6% to 3% in the same scenario and the balance at 65 falls from about $1.59 million to about $930,000. Part of that gap is your own missing contributions, but half the match disappears too: $68,000 of free employer money over the career, plus everything it would have grown into. A 50% match is an instant 50% return on each matched dollar before the market does anything. No index fund, rental property, or savings account competes with that.
If money is tight, the order most planners suggest is: contribute enough to get the full match, pay off high-interest debt such as credit cards, build an emergency fund, then raise your 401(k) rate or fund an IRA. Check your plan's vesting schedule too. Match money often vests over three to six years, and leaving before you are vested forfeits part of it.
2026 limits and catch-up contributions
For 2026 the IRS employee deferral limit is $24,500. Workers 50 and older can add an $8,000 catch-up, for $32,500 total. SECURE 2.0 created a higher catch-up for ages 60 through 63: $11,250 in 2026, for a total of $35,750. At 64 it drops back to the regular $8,000. The calculator applies these amounts by age when the catch-up box is checked, and holds them at 2026 levels for future years, which slightly understates what you could contribute since the limits rise with inflation.
Employer contributions do not count against the $24,500 employee limit; they fall under a much higher combined cap on total annual additions. If you change jobs mid-year, the employee limit applies across all your 401(k) plans combined, so track your year-to-date deferrals yourself.
Assumptions that move the result most
Return rate is the biggest lever. The default scenario ends at about $1.89 million at 7%, $1.53 million at 6%, and $1.25 million at 5%. Two percentage points of return cost more than $600,000 over 35 years. Use 5% or 6% if you want a conservative plan, especially if your portfolio holds a lot of bonds. Fees count here as well: a fund charging 0.75% a year effectively turns a 7% return into 6.25%.
Raises matter more than people expect, because your contribution is a percentage of pay. A 3% raise assumption grows your yearly deposit automatically. Starting age matters most of all. A 45-year-old with nothing saved, a $100,000 salary, and a 10% contribution reaches about $670,000 by 65 with the same match and return. Twenty years is not enough time for growth to do the heavy lifting.
Traditional or Roth 401(k)?
The calculator shows a pre-tax balance. With a traditional 401(k) you get a tax deduction now and pay ordinary income tax on withdrawals. With a Roth 401(k) you pay tax now and qualified withdrawals are tax-free. If you expect a higher tax rate in retirement than today, Roth usually wins; if lower, traditional does. Many people split contributions to hedge. Either way, the employer match goes in as pre-tax money unless your plan offers Roth matching. This is an educational projection, not financial advice.
How we calculate: sources
Frequently asked questions
How does a 401(k) employer match work?
The most common formula is 50% of what you contribute, up to 6% of salary. On a $75,000 salary, contributing 6% puts in $4,500 and your employer adds $2,250. Contribute only 3% and the match drops to $1,125, so you forfeit $1,125 a year of free money.
What is the 401(k) contribution limit for 2026?
$24,500 in employee deferrals for 2026, up from $23,500 in 2025. Workers 50 and older can add an $8,000 catch-up ($32,500 total), and workers aged 60 to 63 get a higher $11,250 catch-up ($35,750 total). Employer match does not count toward the $24,500.
How much will my 401(k) be worth if I start at 30?
With the calculator's defaults ($25,000 saved, $75,000 salary, 8% contribution, 50% match up to 6%, 3% raises, 7% return), the projected balance at 65 is about $1.89 million in future dollars. Lower the return to 5% to see a more conservative case.
How much should I contribute to my 401(k)?
At minimum, enough to get the full employer match, since that is an instant 50% to 100% return. Many planners suggest saving 15% of pay for retirement including the match. If that is out of reach, raise your rate 1 point a year until you get there.
What happens if I contribute more than the 401(k) limit?
Excess deferrals should be returned by April 15 of the following year. If they are not, the excess is taxed in the year you contributed it and again when withdrawn. Payroll systems usually stop you at the limit, but it can happen if you change jobs mid-year.
What rate of return should I use?
Many people use 5% to 7% a year for a diversified, stock-heavy portfolio over decades. Using 7% on nominal returns and then adjusting for inflation is common. Returns are never guaranteed, and fund fees of 0.5% to 1% a year reduce them directly.
Does this calculator include taxes and inflation?
No. Balances are shown in future dollars before income tax. Traditional 401(k) withdrawals are taxed as income; Roth 401(k) withdrawals are tax-free if qualified. Use the inflation calculator to convert the result into today's purchasing power.
Is my data uploaded?
Everything runs in your browser. Nothing you enter is uploaded to a server or stored by us.
How much should I have in my 401(k) by age 40?
A common benchmark is about three times your salary by 40, six times by 50, and ten times by 67. On a $75,000 salary that is $225,000 at 40. Treat it as a rough check, not a rule.
Can I contribute to a 401(k) and an IRA in the same year?
Yes. The IRA limit for 2026 is $7,500, separate from the 401(k) limit. Deducting traditional IRA contributions can be limited by income if you have a workplace plan.