Free 401(k) Calculator
Your 401(k) balance at retirement depends on three things: how much you put in, what your employer adds, and how long compounding works. Enter your details below to project your balance year by year, including the free money from your employer match.
This free 401(k) calculator projects your retirement balance with yearly compounding. For example, a 30-year-old earning $75,000 who contributes 10 percent with a 4 percent employer match and a 7 percent average return could have about $1.82 million by age 65, with employer matches contributing $105,000 of that total. Results assume steady contributions and returns, which never happen perfectly in real life.
Estimates only. Actual returns vary year to year and this tool assumes one constant rate, which is a simplification. Contribution limits and tax rules change; check current IRS guidance. Not financial advice.
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How 401(k) growth math works
A 401(k) grows through yearly compounding on two streams of money: your contributions and your employer's match. Each year, you add a percentage of your salary, your employer adds its match, and the whole balance grows by the assumed return. The formula applied each year is: new balance = (old balance + yearly contributions) x (1 + return).
The employer match is the highest-return part of the whole plan. A common match is 50 cents on the dollar up to 6 percent of salary, which is an instant 50 percent return on those dollars before any market growth. Skipping the match is leaving guaranteed money on the table.
Time does most of the heavy lifting. At a 7 percent return, money roughly doubles every 10 years. A dollar contributed at age 30 is worth about 10 times more at 65 than a dollar contributed at 55, which is why starting early beats contributing more later.
401(k) calculator questions
How much should I contribute to my 401(k)?
Contribute at least enough to capture the full employer match, often around 6 percent of salary, because that is an instant return no investment can beat. From there, a common target is 15 percent of gross income toward retirement, counting both your contributions and the match. If that feels steep, start at the match and raise your rate 1 point each year until you hit 15.
How does the 401(k) employer match work?
Employers usually match a percentage of what you contribute, up to a cap expressed as a percent of salary. A common formula is 50 cents per dollar up to 6 percent of salary. On a $75,000 salary, contributing 6 percent ($4,500) earns a $2,250 match. Contribute less than 6 percent and you leave part of the match unclaimed.
What is a good 401(k) balance by age?
Fidelity publishes widely used benchmarks: about 1 times your salary saved by 30, 3 times by 40, 6 times by 50, 8 times by 60, and 10 times by 67. Treat them as checkpoints, not verdicts. Late starters can still close the gap with higher contributions, and high earners may need different targets.
What return should I assume for my 401(k) projection?
Historical US stock returns average near 10 percent before inflation, but a blended 401(k) portfolio with bonds usually projects at 6 to 8 percent nominal. Using 7 percent is a reasonable middle case. Always run a pessimistic case too, because a 2-point lower return over 30 years cuts the final balance nearly in half.