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401(k) Calculator

Estimate how much your 401(k) retirement savings will grow over time.
Decision Context
Page-specific guidance for using this result in a real planning decision.

This page is designed to project workplace retirement savings with contribution rate, employer match, and investment-growth assumptions.

Use it to compare match strategies, deferral percentages, and time horizons when deciding how aggressively to fund retirement through payroll.

The most important insight is often how much of the ending balance comes from employer match and compounding, not just from your direct contributions.

Calculator
Enter your values

Employer Match Settings

(e.g., 50% or 100%)

(e.g., up to 6%)

Analysis
Interpretation of the current calculator output

Enter values to see detailed analysis and insights.

How to Use

Step-by-step instructions
  1. 1Enter your current age and planned retirement age.
  2. 2Input your current 401(k) balance and salary.
  3. 3Set your expected annual salary increase percentage.
  4. 4Add your 401(k) contribution rate and your employer's match strategy.
  5. 5Adjust your expected rate of return to project the final balance.

Compound Growth with Annual Contributions

Your 401(k) grows from your starting principal (P), plus the future value of your ongoing annual contributions (PMT) including employer match, all compounding at your expected rate of return (r) over time (t).
FV = P(1+r)^t + PMT[((1+r)^t - 1) / r]

Variables:

FVFuture Value of account
PMTTotal annual contributions (You + Employer)
rAnnual rate of return

Example

Typical 401k Growth

Inputs:

Salary:$80k
Contributions:8%
Match:50% up to 6%
Return:7%

Steps:

  1. 1.Employee contributes 8% ($6,400/yr).
  2. 2.Employer matches 50% of the first 6% ($2,400/yr).
  3. 3.Total annual deposit is $8,800/yr.
  4. 4.Balance compounds at 7% per year, scaling as salary increases.
Result:
Compound interest heavily outperforms the base contributions.

Frequently Asked Questions

What does '50% match up to 6%' mean?

It means if you contribute 6% of your salary, your employer will add half of that amount (3% of your salary) for free. If you contribute more than 6% (e.g., 8%), they still max out at giving you that same 3%.

What is a realistic expected return?

Historically, the stock market has returned around 10% annually before inflation, or roughly 7% adjusted for inflation. A 7% expected return is a common conservative benchmark.