401(k) Calculator
Estimate your 401(k) balance at retirement based on your salary, contribution rate, employer match, and expected investment returns. See year-by-year growth projections.
% of your contribution matched
Employer matches up to this %
Understanding Your 401(k): The Most Powerful Retirement Savings Tool
The 401(k) plan is the most common employer-sponsored retirement account in the United States, covering over 60 million active participants and holding more than $7.7 trillion in assets as of 2024 (Investment Company Institute). Named after Section 401(k) of the Internal Revenue Code, it allows employees to save and invest a portion of their paycheck before taxes are taken out, reducing their current taxable income while building wealth for retirement.
The employer match is what makes the 401(k) uniquely powerful. When your employer matches your contributions, they are literally giving you free money. The most common match formula is 50 cents on the dollar up to 6% of salary, meaning if you contribute 6% of a $75,000 salary ($4,500), your employer adds $2,250 for a total of $6,750. Not contributing enough to get the full match is equivalent to leaving part of your salary on the table.
This calculator models the combined power of your contributions, employer matching, salary growth, and compound investment returns over time. Even a 1% increase in your contribution rate today can add tens of thousands of dollars to your retirement balance. To see how contributions affect your paycheck, use our Paycheck Calculator.
2025 401(k) Contribution Limits
| Limit Type | 2025 Limit | Notes |
|---|---|---|
| Employee Contribution | $23,500 | Salary deferral limit |
| Catch-Up (Age 50+) | +$7,500 | Total employee: $31,000 |
| Total (Employee + Employer) | $70,000 | All sources combined |
| Total w/ Catch-Up (Age 50+) | $77,500 | All sources combined |
| Compensation Cap | $350,000 | Max salary considered for match |
How to Maximize Your 401(k)
Follow this priority order to get the most from your 401(k):
1. Contribute Enough to Get the Full Employer Match
This is the most important step. If your employer matches 50% up to 6%, contribute at least 6%. The match is an immediate 50% return on your money, which you will never find in any other investment. Not contributing enough for the full match means you are turning down part of your compensation package.
2. Increase Your Contribution by 1% Each Year
Most people do not feel a 1% contribution increase in their paycheck, especially when paired with an annual raise. Going from 6% to 15% over 9 years can add hundreds of thousands to your retirement balance. Many 401(k) plans offer an auto-escalation feature that increases your contribution automatically each year.
3. Choose Low-Cost Index Funds
Fund expense ratios directly reduce your returns. A 0.05% index fund versus a 1.0% actively managed fund means an extra 0.95% in annual returns staying in your account. On a $500,000 balance, that difference is $4,750 per year. Target-date funds are a good default option for most investors who want a hands-off approach.
4. Consider Roth 401(k) Contributions
If you are early in your career and in a low tax bracket, Roth 401(k) contributions (post-tax) may be better than traditional (pre-tax). You pay taxes now at a low rate and withdraw tax-free in retirement when your income may be higher. Having both traditional and Roth savings gives you tax diversification in retirement. See how Roth vs Traditional affects your take-home with our Net Pay Calculator.
The Impact of Employer Match: Real Numbers
To illustrate how much the employer match matters, here is a comparison of two scenarios for a 30-year-old earning $75,000 with a 3% annual raise and 7% investment returns, contributing 6% to their 401(k) over 35 years to age 65:
| Scenario | Your Contributions | Employer Match | Balance at 65 |
|---|---|---|---|
| No Employer Match | $270,450 | $0 | $845,000 |
| 50% Match up to 6% | $270,450 | $135,225 | $1,267,500 |
| 100% Match up to 6% | $270,450 | $270,450 | $1,690,000 |
The employer match in the 100% scenario adds $845,000 to the retirement balance despite only contributing $270,450 in matching funds. The difference is compound growth on those matching contributions over 35 years. This is why experts call the employer match the best deal in personal finance.
Common 401(k) Mistakes to Avoid
- Not contributing enough for the full match: About 1 in 5 employees leave employer match money on the table (Vanguard, 2024). This is the equivalent of refusing a pay raise.
- Cashing out when changing jobs: Nearly 40% of workers cash out their 401(k) when leaving a job instead of rolling it over. Early withdrawals trigger income taxes plus a 10% penalty, often consuming 30-40% of the balance.
- Being too conservative: Young workers with decades until retirement should have 80-100% in stock funds. Being overly conservative costs growth. A portfolio earning 5% instead of 7% over 35 years results in 40% less money at retirement.
- Taking 401(k) loans: While technically borrowing from yourself, 401(k) loans remove money from the market during the loan period, costing you compound growth. If you leave your job, the full balance is typically due within 60 days or it becomes a taxable distribution.
- Ignoring expense ratios: Some 401(k) plans offer funds with 1%+ expense ratios when similar index funds charge 0.03-0.10%. Over 30 years, the difference on a $500,000 balance can exceed $100,000.
401(k) Vesting Schedules: When Employer Matches Are Truly Yours
While your own contributions are always 100% yours, employer matching contributions are subject to a vesting schedule. Vesting determines how much of the employer match you keep if you leave the company before a certain number of years. The two most common vesting schedules are:
| Years of Service | Cliff Vesting | Graded Vesting |
|---|---|---|
| 1 year | 0% | 0% |
| 2 years | 0% | 20% |
| 3 years | 100% | 40% |
| 4 years | 100% | 60% |
| 5 years | 100% | 80% |
| 6 years | 100% | 100% |
Understanding your vesting schedule is important when considering a job change. If you are close to a vesting cliff, staying a few more months could mean keeping thousands in employer match dollars. Always check your plan documents or HR department for your specific vesting schedule. For comparing total compensation between job offers including 401(k) benefits, use our Job Offer Comparison tool.