401k Retirement Calculator
Estimate your 401(k) balance at retirement by factoring in your salary, contribution rate, employer match, and expected investment returns. Use this when planning how much to save each year.
About this calculator
A 401(k) grows through annual contributions that are invested and compound over time. Each year, your contribution equals your salary × (contribution% / 100). Your employer may match a portion of that — the match factor is min(employerMatch / 100, 1). The total annual deposit is then: annual_deposit = salary × (contribution / 100) × (1 + min(employerMatch / 100, 1)). This deposit is treated as an annuity growing at your expected annual return rate r over (retirementAge − currentAge) years. The future value formula is: FV = annual_deposit × ((1 + r)ⁿ − 1) / r, where r = returnRate / 100 and n = retirementAge − currentAge. The result shows the lump-sum balance you could have on your retirement date, assuming consistent contributions and returns.
How to use
Suppose you are 30 years old, plan to retire at 65, earn $70,000/year, contribute 6%, your employer matches 50%, and you expect a 7% annual return. Annual deposit = $70,000 × 0.06 × (1 + 0.50) = $6,300. n = 65 − 30 = 35 years, r = 0.07. FV = $6,300 × ((1.07³⁵ − 1) / 0.07) = $6,300 × 138.24 ≈ $870,912. That means consistent 6% contributions with a 50% employer match could grow to roughly $870,900 by retirement.
Frequently asked questions
How does employer matching affect my 401(k) balance at retirement?
Employer matching directly multiplies your effective annual contribution. If your employer matches 50% of your contribution, every dollar you put in becomes $1.50 invested. Over decades of compounding, this difference is enormous — in a 35-year scenario at 7% return, a 50% match can add hundreds of thousands of dollars to your final balance. Always contribute at least enough to capture the full employer match, as it is essentially free money.
What annual return rate should I use for a 401(k) retirement projection?
A commonly used long-term assumption is 6–8% per year, reflecting a diversified mix of stocks and bonds. The U.S. stock market has historically averaged around 10% annually before inflation, but most retirement planners use a more conservative figure to account for bond allocations and market volatility. Your actual return will depend on your fund choices, fees, and market conditions, so running the calculator with multiple rate scenarios is a smart approach.
When should I increase my 401(k) contribution rate?
You should review your contribution rate whenever you receive a raise, change jobs, or hit a major life milestone. A common guideline is to increase contributions by 1% each year until you reach the IRS annual limit ($23,000 in 2024). Even small increases early in your career have an outsized impact because of compounding over a long time horizon. If you are behind on retirement savings, maximizing contributions as soon as possible is the most effective catch-up strategy.