Project what your workplace retirement account could grow into. Enter your salary, contribution rate, employer match and expected return to see the balance at retirement — and the free money matching adds.
Answer first: a 401(k) grows from three engines — the money you contribute, the money your employer adds through matching, and decades of compound growth on top. This 401(k) calculator works out your annual contribution and employer match, then projects the whole balance forward using compound interest so you can see roughly where you might land at retirement.
Employer match = Match rate × min(your rate, match limit) × salary
Future balance = Current balance × (1 + r)ⁿ + Annual contribution × [((1 + r)ⁿ − 1) ÷ r]
Example: a $70,000 salary, contributing 6% ($4,200) with a 50% match up to 6% (a $2,100 employer top-up), starting from $20,000, growing 7% a year for 30 years, projects to roughly $747,000.
The single most important line in that example is the employer match. A 50% match on your first 6% is an instant, guaranteed 50% return on that money before the market does anything at all — the closest thing to free money in personal finance. Contributing at least enough to capture the full match is close to a universal rule of thumb, because leaving it on the table is turning down part of your own pay packet.
Notice in the example that a $6,300 annual contribution over 30 years — about $189,000 of actual deposits — grows into roughly $747,000. The other half-million-plus is pure compound growth: returns earning returns, year after year. That is why time in the market matters so much more than timing it, and why a dollar invested at 25 is worth vastly more at retirement than a dollar invested at 45. Use the compound interest calculator to see the same force in isolation.
Most 401(k) plans offer two flavours. A traditional 401(k) uses pre-tax money, cutting your tax bill today, but withdrawals in retirement are taxed. A Roth 401(k) uses after-tax money, so qualified withdrawals later are tax-free — often the better deal if you expect to be in a higher bracket in retirement or have decades of growth ahead. Either way, the IRS caps how much employees can contribute each year, with an extra catch-up allowance for those age 50 and over. Those limits change annually, so confirm the current figures at irs.gov before maxing out. This calculator does not enforce the cap, so keep your contribution within the current limit for a realistic projection.
Treat the result as a ballpark, not a promise. Real markets do not deliver a smooth 7% every year — they lurch up and down, and the order of good and bad years matters, especially near retirement. Inflation quietly erodes the purchasing power of that future balance, so a projected $747,000 will buy less then than it would today; the inflation calculator shows by how much. And your salary, contribution rate and returns will all change over the years. The value of the exercise is not the exact number but the lesson it teaches: start early, always capture the full match, and let compounding run.
Reality check: this is a simplified projection assuming a constant return and steady contributions; it ignores taxes, fees, salary changes and market volatility, and does not enforce IRS limits. It is educational, not financial or tax advice. See investor.gov and irs.gov for the rules.
Explore the growth engine with the compound interest calculator, plan the finish line with the retirement savings and 4% rule calculators, and compare account types with the Roth vs traditional IRA guide.
Last updated July 4, 2026 · Written by Mustafa Bilgic. Educational only — not financial advice.
At a minimum, contribute enough to capture your full employer match — that is an immediate, guaranteed return on your money. Many planners suggest aiming for 10%–15% of salary including the match, but the right figure depends on your budget and goals.
An employer typically matches a percentage of your contributions up to a limit — for example, 50% of what you put in, up to 6% of your salary. On a $70,000 salary that adds $2,100 a year of free money if you contribute at least 6%.
The IRS sets an annual employee contribution limit, with an extra catch-up amount for those age 50 and over. These limits change every year, so check the current figures at irs.gov. This calculator does not enforce the cap.
A traditional 401(k) lowers your taxes now but taxes withdrawals later; a Roth 401(k) uses after-tax money for tax-free withdrawals in retirement. A Roth often wins if you expect higher taxes later or have decades of growth ahead.