Retirement Planning
401(k)
Calculator
See how your 401(k) grows over time with employer matching and compound returns. Enter your details to project your retirement balance.
Your Details
Employer Match
e.g. 50 = 50¢ per $1
e.g. 6 = up to 6%
Growth Assumptions
Enter your details and click calculate to see your projected 401(k) balance at retirement.
What is a 401(k)?
A 401(k) is a tax-advantaged retirement savings plan sponsored by US employers. Named after section 401(k) of the Internal Revenue Code, it allows employees to contribute pre-tax income directly from their paycheck. Contributions grow tax-deferred — you don't pay tax until you withdraw in retirement. Many employers sweeten the deal with matching contributions, making the 401(k) one of the most powerful wealth-building tools available to American workers.
The growth formula
2025 401(k) contribution limits
| Under 50 | 50 and over | |
|---|---|---|
| Employee limit | $23,500 | $31,000 |
| Total limit (incl. employer) | $70,000 | $77,500 |
| IRA limit | $7,000 | $8,000 |
Frequently asked questions
What is a 401(k)?
A 401(k) is a tax-advantaged retirement savings plan offered by US employers. You contribute pre-tax dollars (traditional) or after-tax dollars (Roth), reducing your taxable income now or in retirement. Many employers match a percentage of your contributions — that match is essentially free money.
How much should I contribute to my 401(k)?
At minimum, contribute enough to get your full employer match — otherwise you're leaving free money on the table. Beyond that, the general rule is to save 15% of your gross income for retirement (including employer match). The 2025 IRS contribution limit is $23,500 for employees under 50, and $31,000 for those 50 and over (catch-up contributions).
What is employer matching?
Employer matching is when your company contributes to your 401(k) based on what you put in. A common match is 50% of your contributions up to 6% of salary — meaning if you earn $80,000 and contribute 6% ($4,800), your employer adds $2,400. Always contribute at least enough to get the full match.
What rate of return should I use?
The US stock market has historically returned around 7–10% annually before inflation, or roughly 5–7% after inflation. A conservative estimate is 6%, moderate is 7–8%, and optimistic is 10%. The calculator defaults to 7% as a reasonable long-term average for a diversified portfolio.
What's the difference between traditional and Roth 401(k)?
Traditional 401(k): contributions are pre-tax, reducing your taxable income now — you pay tax when you withdraw in retirement. Roth 401(k): contributions are after-tax — withdrawals in retirement are completely tax-free. Roth is generally better if you expect to be in a higher tax bracket in retirement.
Related calculators
Mandeep Singh · 25+ Years UK Financial Services
Important Information
This calculator is for informational purposes only and does not constitute financial advice, a personal recommendation, or an offer to buy or sell any investment or asset class.
Projected figures are illustrative estimates based solely on the inputs you provide. Returns are not guaranteed and actual outcomes will differ.
Past performance is not a guide to future performance, nor a reliable indicator of future results.
If you are unsure about the suitability of any investment or savings strategy for your circumstances, you should seek independent advice from a qualified financial adviser.