US 401(k) Calculator
See what your 401(k) could grow to by retirement, how much your employer adds, what you'd miss without the full match and the monthly income it could give you.
The box above is then your pre-tax 401(k). Both count towards the same IRS limit.
Paid whether or not you contribute, e.g. a 3% safe harbor contribution.
2026: $24,500 for you, +$8,000 at 50+, or +$11,250 at 60–63; $72,000 with your employer's money; pay counted up to $360,000.
Your average rate on pre-tax money you take out.
The 4% rule is a common starting point.
Year-by-year table and chart
| Year · age | Pay | You | Employer | Growth − fees | Balance | Today's $ |
|---|
* You hit the IRS limit that year, so what you put in stops at the limit.
How your 401(k) is worked out
What goes in each year, plus the match, grows until you retire.
- 1
You put in
$75,000 × 6%= $4,500
- 2
Employer match
50% × 6%× $75,000= $2,250
- 3
Growth to 67
37 years at 7%− 0.5% feespay +3% a year= $1,692,999
- 4
Monthly income
$1,692,999 × 4%÷ 12= $5,643 a month$2,263 today
Read more: the formula, a worked example, 2026 limits and the match
A 401(k) is a workplace retirement plan. You put in a share of each paycheck, your employer often adds a match, and the money is invested until you retire. Pre-tax money lowers your tax bill now and is taxed when you take it out; Roth money is taxed now and comes out tax-free later if the rules are met.
The formula
your contribution = pay × your % (stops at the IRS limit)
match = pay × match rate × (your %, up to the match limit)
each month: balance × (1 + monthly return − fee ÷ 12) + this month's contributions
monthly return = (1 + yearly return)^(1/12) − 1
today's dollars = balance ÷ (1 + inflation)^years
monthly income = balance × withdrawal rate ÷ 12
Worked example
You are 30, earn $75,000 a year and put in 6%: $4,500 this year. Your employer matches 50% of the first 6% of pay: 50% × 6% × $75,000 = $2,250. So $6,750 goes in this year, paid in monthly. Your $25,000 grows at 7% a year (0.5654% a month) less fees of 0.5% ÷ 12 = 0.0417% a month, so the year ends at $33,565.
Each year your pay rises 3%, so the amounts going in rise too. After 37 years, at 67, the balance is $1,692,999. You put in $297,784, your employer added $148,892, and growth after $97,162 of fees made up the rest. At 2.5% inflation that is $679,006 in today's dollars. At a 4% withdrawal rate it gives $1,692,999 × 4% ÷ 12 = $5,643 a month, or about $2,263 a month in today's dollars. The 0.5% fees cost you $220,977 by retirement compared with no fees.
2026 IRS limits
| Your contributions (pre-tax + Roth) | $24,500 |
|---|---|
| Catch-up at age 50 or over | +$8,000 |
| Catch-up at ages 60 to 63 (instead) | +$11,250 |
| You + employer (not counting catch-ups) | $72,000 |
| Pay that can be counted | $360,000 |
| Catch-ups must be Roth if last year's pay was over | $150,000 |
The calculator treats you as your age now plus the years from now for the whole year. It raises the limits each year with your inflation rate, rounded down like the IRS does, unless you choose to keep the 2026 limits.
Money left on the table
If you put in less than the match limit, you give up free money. With a 50% match up to 6%, putting in 3% of $75,000 gets $1,125 from your employer instead of $2,250. The calculator shows what you miss this year, and in Advanced mode what all the missed match would have grown to by retirement.
Things to know
- The match is worked out on the whole year. If your plan matches each paycheck and has no "true-up", hitting the limit early in the year can cost you some match.
- Employer money usually vests over a few years. Leave before it vests and you may lose some of it.
- Taking money out before 59½ usually means income tax plus a 10% extra tax, with some exceptions.
- Returns are not guaranteed. A steady 7% is a planning number, not a promise.
2026 limits from the IRS (irs.gov). Check the latest figures before you decide. This is an estimate, not financial advice.
Common questions
What is the 401(k) contribution limit for 2026?
You can put in up to $24,500 in 2026, pre-tax and Roth together. If you are 50 or older you can add a $8,000 catch-up, and at ages 60 to 63 the catch-up is $11,250 instead. Your money plus your employer's can't pass $72,000, not counting catch-ups. Check the latest figures on irs.gov.
How does a 401(k) employer match work?
A common match is 50% of what you put in, up to 6% of your pay. On $75,000 of pay, putting in 6% ($4,500) gets you $2,250 from your employer. Put in only 3% and you get $1,125, leaving $1,125 a year on the table. Advanced mode handles two-tier matches too.
How much will my 401(k) be worth when I retire?
With the default numbers here, a 30-year-old earning $75,000 who puts in 6% with a 50% match up to 6%, starts with $25,000 and earns 7% a year less 0.5% fees, with pay rising 3% a year, would have about $1.69 million at 67. That is about $679,000 in today's dollars at 2.5% inflation.
Should I choose a Roth 401(k) or a pre-tax 401(k)?
Pre-tax money lowers your tax bill now, but you pay income tax when you take it out. Roth money is taxed now and comes out tax-free in retirement if the rules are met. If you expect a lower tax rate in retirement, pre-tax tends to win; if higher, Roth tends to win. You can split between both.
How much tax does a 401(k) save?
Pre-tax contributions come off your taxable pay. At a 22% federal bracket plus 5% state tax, putting $4,500 in saves about $1,215 of income tax this year. Social Security and Medicare tax are still due on that money. Roth contributions don't save tax now.
How much monthly income will my 401(k) give me?
A simple rule is to take about 4% of your balance in the first year of retirement. A $1,692,999 balance at 4% gives about $67,720 a year, or $5,643 a month, before tax. Pre-tax money is taxed as income when you take it out.
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Made by Zulu Calculator, part of AlphaZulu LLC. Formulas are shown in full and rule figures are checked against official sources; see how we build calculators.