401(k) Calculator

This calculator estimates how your 401(k) balance may grow from today until retirement. It combines your current age, salary, existing 401(k) balance, and contribution rate with employer matching and expected investment returns. It also lets you include salary raises and inflation, so you can view results in future dollars and "today's dollars." This tool helps employees who want a clearer retirement target, anyone comparing different contribution rates, and people deciding whether to retire earlier or later. The result you get is a projected balance at retirement (and often a breakdown of contributions, match, and growth).

How to Use This Calculator

1. Enter your current age.
2. Add your current annual salary and your current 401(k) balance.
3. Set your contribution percent (how much of your salary you contribute).
4. Enter your employer match percent and match limit (if your employer offers one).
5. Choose your retirement age and life expectancy (for planning how long money may need to last).
6. Add annual salary increase, expected annual return, and inflation rate.
7. Click Calculate to see your projected results.
8. Adjust one input at a time (like contribution rate or retirement age) to compare scenarios.

What This Calculator Measures

This 401(k) calculator projects the future value of your retirement account based on the information you enter.

Key terms in simple language:

• 401(k) balance: The money currently in your 401(k).
• Contribution percent: The share of your salary you put into the plan.
• Employer match: Extra money your employer adds when you contribute.
• Match limit: The maximum salary percent your employer will match.
• Expected annual return: Your estimated investment growth rate each year.
• Salary increase: The yearly raise you expect, which can increase contributions over time.
• Inflation rate: How much prices rise over time; it reduces future buying power.
• Retirement age: When you plan to stop working and contributing.

Formula or Logic (Easy Explanation)

The calculator works like a year-by-year forecast:

• It starts with your current 401(k) balance.
• Each year, it adds your employee contributions (based on salary × contribution percent).
• If you have a match, it adds employer contributions (based on match rules and limits).
• Then it applies investment growth to the total (using your expected return).
• It repeats this process until your retirement age.
• If inflation is included, it also shows what that future amount may be worth in today's dollars.

Example Calculations

Example 1: Early career saver with an employer match

• Current age: 25
• Salary: $55,000
• Current 401(k) balance: $5,000
• Contribution: 8%
• Employer match: 50% up to 6%
• Retirement age: 65
• Salary increase: 3%
• Expected return: 7%
• Inflation: 2.5%

Output (estimate): A projected retirement balance plus a breakdown showing what you contributed, what your employer added, and what growth contributed.

Example 2: Mid-career catch-up through a higher contribution

• Current age: 40
• Salary: $95,000
• Current 401(k) balance: $120,000
• Contribution: 12%
• Employer match: 100% up to 4%
• Retirement age: 67
• Salary increase: 2%
• Expected return: 6%
• Inflation: 2.5%

Output (estimate): A higher projected balance, often driven by a larger yearly contribution and continued compounding.

Example 3: Comparing retirement ages

Use the same inputs, but run two scenarios:

• Scenario A retirement age: 62
• Scenario B retirement age: 67

Output (estimate): Scenario B typically shows a larger balance because you add more contributions and give investments more time to grow.

Understanding Your Results

Your results usually include:

• Projected balance at retirement: The total amount you may have by your retirement age.
• Total contributions: What you put in from paychecks over the years.
• Employer match total: What your employer may add (if applicable).
• Investment growth: The increase from compounding returns over time.
• Inflation-adjusted value (if shown): A "today's dollars" view that helps you judge buying power.

If your projected balance feels low, the biggest levers are usually:

• Increasing your contribution percent
• Capturing the full employer match
• Extending your time to retirement
• Using more conservative or more realistic return and inflation assumptions

Common Mistakes to Avoid

• Entering a match rate but forgetting the match limit.
• Using an overly optimistic expected return without testing a conservative case.
• Leaving salary increase at 0% when you expect raises.
• Ignoring inflation, then overestimating real buying power.
• Confusing contribution percent with a fixed dollar amount.
• Forgetting to update inputs after a job change or pay increase.
• Assuming results are guaranteed (they are estimates, not promises).
• Setting retirement age without considering how long savings may need to last.