401k Contribution Calculator
Model your 401k growth, including the powerful impact of an employer match. See how your contributions, match, and investments add up over time.
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Enter your details and click Calculate.
Understanding Your 401k
What is a 401k?
A 401k is an employer-sponsored retirement savings plan. It allows you to invest a portion of your paycheck directly into investments, often on a pre-tax basis. This means your contributions lower your taxable income today, and your investments grow "tax-deferred" — you don't pay any taxes on the growth year after year. Unsure if pre-tax is right for you? Compare with our Roth vs. Traditional Calculator.
The Power of the Employer Match
This is the most powerful feature of a 401k. Many employers offer a "match" to incentivize you to save. A common example is "50% match up to 6% of your salary."
- This means if you contribute 6% of your salary, your employer will add *another* 3% (50% of your 6%) for free.
- This is an immediate, guaranteed 50% return on your investment, up to the match limit. Comparing job offers with different matches? Use our Job Offer Comparator.
- Rule of Thumb: You should *always* contribute at least enough to get the full employer match. Not doing so is like turning down free money.
How This Calculator Works
This tool models your 401k growth based on several key factors:
- Your Contributions: Calculated as a percentage of your salary.
- Employer Contributions: Calculated based on your contribution and your employer's match rules.
- Compounding Growth: Your existing balance, plus all new contributions, are grown year after year based on your "Estimated Annual Return."
The chart shows how your balance accelerates over time, with the interest earned eventually becoming a larger driver of growth than your own contributions. Curious how fees affect this growth? Check out the Investment Fee Analyzer.
💡 Which account is better?
Compare taxes now (Traditional) vs. taxes later (Roth).