401(k) Calculator (Growth + Employer Match)
Enter your salary, contribution percentage, and your employer's match terms. You'll see your projected balance at retirement, what the match adds every year, and exactly what skipping any of it costs.
Gross, before taxes
Percent of salary you defer each paycheck
Of your contribution. 50% means 50 cents per dollar
The share of salary your plan matches up to
After inflation. 5% is a common long-run assumption
Balance at retirement
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Enter your salary and age
Free money from the match
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Leaving match on the table?
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The match is an instant 50-100% return
No investment reliably pays 50% on the day you make it, except this one. When your employer matches 50 cents per dollar up to a share of your salary, every matched dollar earns half its value back immediately, before any market growth, and a dollar-for-dollar match doubles your money on contact. That's why "contribute at least to the full employer match" is the rare piece of money guidance nobody argues with. The one asterisk is vesting: in some plans the employer's dollars become fully yours only after a few years of service, so the match is free money with a loyalty clause.
Think in percent of salary, not dollars
Plans define everything in percentages for a reason: a percentage scales itself. A 6% contribution set once keeps pace with every raise, while a fixed dollar amount quietly shrinks relative to your income each year. The match limit is a percent of salary too, which makes the key threshold easy to remember: your contribution percentage should never sit below the match limit percentage, because the gap between them is compensation you earned and declined. The IRS does cap what you can defer in a year, and the cap changes annually, so this calculator deliberately deals in percentages and mechanics rather than any single year's dollar figure. Where the deferral fits among your other priorities is the subject of our save-or-invest guide.
The match follows the job, the balance follows you
Change jobs and your vested balance stays yours. You can usually leave it in the old plan, move it to the new one, or do a rollover into an IRA, and the compounding continues either way. The real risk is quieter: after two or three employers, people lose track of old accounts entirely, and a forgotten balance is a forgotten piece of your net worth. Keeping every account, old plans included, in one live picture is exactly what Stoia is built for. And once the match is captured, the next question is whether those deferrals should be Roth or traditional, which the Roth vs. traditional calculator settles with your own tax rates.
Frequently asked questions
How does a 401(k) employer match work?
Your employer adds money when you contribute, on defined terms. A typical formula: 50% of your contribution, up to 6% of salary. Contribute 6% of a $90,000 salary ($5,400) and the employer adds $2,700 on top. Contribute less than the limit and the employer's addition shrinks with yours; contribute more and the extra is unmatched but still grows.
How much should I contribute to my 401(k)?
At minimum, enough to capture the full match, since that part earns an immediate return no investment can promise. Beyond the match, more is generally better if your budget allows. The IRS caps employee contributions each year and the cap adjusts annually, so if your percentage works out to a large dollar amount, check the current limit.
What does '50% match up to 6%' actually mean?
Two numbers, two jobs. The 50% is the match rate: for each dollar you contribute, the employer adds 50 cents. The 6% is the ceiling: only your contributions up to 6% of salary get matched. So the maximum employer money is 50% of 6% of salary, or 3% of pay per year.
Is the match really free money?
Effectively yes, with one caveat: vesting. Your own contributions are always yours, but some plans make employer contributions fully yours only after a set number of years of service. Leave before vesting and you forfeit some or all of the matched dollars.
Does this projection account for taxes and inflation?
It handles inflation by using an after-inflation return, so the ending balance reads in today's purchasing power. It shows the pre-tax account balance: with traditional contributions you'll owe income tax on withdrawals, with Roth contributions you generally won't, which is a separate comparison our Roth vs. traditional calculator handles.
Does this calculator save my numbers?
No. Everything runs in your browser and disappears when you leave. Nothing is uploaded or stored.
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