Free online 401(k) retirement calculator

How to use

1. Enter your current age and the age at which you plan to retire.
2. Enter your current 401(k) balance and annual contribution amount.
3. Set the employer match percentage (e.g., 100 means your employer matches dollar-for-dollar).
4. Adjust the annual return and inflation rate.
5. Click Calculate 401(k) to see your projected balance and the year-by-year table.

The formula

Each year’s balance is calculated as:

balance = (prev_balance + contribution + employer_match) × (1 + return_rate)

The inflation-adjusted (real) balance is:

balance_real = balance / (1 + inflation_rate)^years

Worked example

Age 30, retiring at 65 (35 years). Current balance: $50,000. Annual contribution: $19,500. Employer match: 100%. Annual return: 7%. Inflation: 2.5%.

• Employer adds $19,500/year for 35 years = $682,500 in match (before growth)
• Projected nominal balance at 65: approximately $7.4 million
• In today’s dollars (inflation-adjusted): approximately $3.0 million

The projection illustrates the compounding power of tax-deferred growth and employer match over a long career.

Notes

• This calculator does not model IRS contribution limits, which change annually.
• Withdrawals from traditional 401(k) plans are taxed as ordinary income at retirement. The Roth 401(k) variant allows tax-free withdrawals.
• The 7% return assumption is nominal, not real. If you compare to inflation-adjusted figures, subtract the inflation rate to get the real return.