Retirement Calculator

Plan your retirement by calculating how much you need to save and projecting your income throughout retirement. Consider 401k, IRA, and Social Security benefits.

What Is a Retirement Calculator?

A retirement calculator projects the future value of your retirement savings based on your current balance, regular contributions, employer matching, expected investment returns, and the number of years until you retire. It answers the fundamental question every working person faces: will I have enough money to retire comfortably?

The calculator runs a month-by-month simulation, applying contributions and investment returns to model how your savings grow over time. It accounts for employer matching rules, annual salary increases, and the eroding effect of inflation on purchasing power. The result is a clear picture of your projected retirement fund in both nominal and inflation-adjusted terms.

How Retirement Savings Math Works

Retirement savings growth relies on compound interest, where investment returns generate their own returns in subsequent periods. The process works monthly: your current balance earns a return, your contribution is added, your employer's match is added, and then the new total earns returns the following month.

The monthly return rate is the annual expected return divided by 12. Each month, the balance grows by: New Balance = Previous Balance x (1 + Monthly Rate) + Employee Contribution + Employer Match.

Employer matching typically works as a percentage of your contribution up to a limit tied to your salary. For example, a 50% match on contributions up to 6% of salary means the employer adds $0.50 for every $1.00 you contribute, capped at 6% of your gross pay. Contributions above that 6% threshold receive no additional match.

The 4% rule converts a lump-sum retirement balance into estimated annual income. It is based on research showing that withdrawing 4% of a portfolio in the first year of retirement, then adjusting for inflation each year, has historically sustained portfolios for 30 or more years.

How to Use This Calculator

Enter your current age and target retirement age. The difference determines how many years your money has to grow. A longer time horizon allows more compounding.
Enter your current retirement savings. This is the total balance across all retirement accounts (401k, IRA, Roth IRA, etc.) as of today.
Set your monthly contribution. This is the amount you personally deposit each month into retirement accounts.
Configure employer matching. Enter the match percentage (what fraction of your contribution the employer matches) and the match limit (the maximum percentage of salary eligible for matching).
Enter your annual salary and expected raise. Salary affects the employer match cap and helps project how contributions might grow if you increase them proportionally over time.
Set expected return and inflation rates. The expected annual return reflects your investment portfolio's anticipated growth. Inflation determines the purchasing-power adjustment applied to the final result.
Review the projection. The results show your projected balance, how it breaks down between contributions, employer match, and investment growth, and what income it could support using the 4% withdrawal rule.

Worked Examples

Example 1: Early Career Saver

Age 25, retirement age 65, $10,000 current savings, $400 monthly contribution, 50% employer match up to 6% of a $55,000 salary, 7% expected return, 3% inflation. Over 40 years of aggressive compounding, the projected balance grows substantially. The employer match adds meaningful contributions each year, and investment growth becomes the dominant factor after the first decade.

Example 2: Mid-Career Catch-Up

Age 40, retirement age 67, $120,000 current savings, $800 monthly contribution, 100% employer match up to 4% of $85,000 salary, 6.5% return, 3% inflation. With 27 years of growth, the existing $120,000 base compounds significantly while the increased monthly contributions and full employer match accelerate accumulation.

Example 3: Late Starter

Age 50, retirement age 67, $50,000 current savings, $1,200 monthly contribution, no employer match, 6% return, 3% inflation. With only 17 years, compound growth has less time to work. Higher monthly contributions help compensate, but the final balance will be considerably less than earlier starters.

Example 4: Aggressive Saver

Age 30, retirement age 55, $75,000 current savings, $2,000 monthly contribution, 50% employer match up to 6% of $100,000 salary, 7% return, 3% inflation. The goal of early retirement at 55 means only 25 years of growth but extremely high contributions. The balance must sustain a potentially 35-plus-year retirement.

Tips and Common Mistakes

Maximize your employer match first. Employer matching is an immediate 50% or 100% return on your contributions. Before investing anywhere else, contribute at least enough to capture the full match. Not doing so is leaving free money on the table.

Do not underestimate inflation. A 3% annual inflation rate cuts purchasing power roughly in half over 25 years. Always look at the today's-dollars figure to understand what your savings will actually buy in retirement.

Increase contributions when you get raises. Directing a portion of each salary increase to retirement savings accelerates growth without reducing your current take-home pay relative to what you were earning before the raise.

Be realistic about investment returns. Using an unrealistically high return rate creates a false sense of security. For long-term planning, 6 to 7 percent is a prudent assumption for a diversified portfolio. If you are heavily invested in bonds, use a lower figure.

Review and update annually. Retirement planning is not a one-time exercise. Revisit the calculator each year with updated savings balances, contribution amounts, and salary figures to ensure you remain on track.

Consider tax implications. This calculator projects pre-tax growth. Withdrawals from traditional 401k and IRA accounts are taxed as ordinary income. Roth accounts grow and are withdrawn tax-free. Your actual retirement income depends on the mix of account types you hold.

Frequently Asked Questions

How does the retirement calculator project my savings?

The calculator uses a month-by-month simulation that starts with your current savings, adds your monthly contribution and employer match each month, then applies investment growth at the specified annual return rate divided by 12. It repeats this process for every month until your target retirement age, compounding returns on the growing balance. Salary increases are applied annually, which can affect employer match amounts over time.

What is the 4% rule for retirement withdrawals?

The 4% rule is a widely referenced guideline suggesting that retirees can withdraw 4% of their portfolio balance in the first year of retirement and adjust that amount for inflation each subsequent year, with a high probability that the portfolio lasts 30 years. For example, a $1,000,000 portfolio would support $40,000 in annual withdrawals. This rule is a starting point, not a guarantee, and actual withdrawal rates should account for individual circumstances.

What annual return rate should I use?

A commonly used estimate for a diversified stock-and-bond portfolio is 6 to 8 percent before inflation. The historical average annual return of the S&P 500 is roughly 10 percent before inflation, but a blended portfolio with bonds returns less. A conservative estimate of 6 to 7 percent is reasonable for long-term planning. The calculator also adjusts for inflation to show results in today's dollars.

How does employer matching work?

Employer matching means your employer contributes additional money to your retirement account based on your own contributions. A common structure is a 50% match on contributions up to 6% of salary. For example, if you earn $65,000 and contribute 6% ($3,900), your employer adds 50% of that ($1,950). This is essentially free money and should be maximized whenever possible.

Why does the calculator show two dollar amounts?

The calculator shows both the nominal (future) value and the inflation-adjusted (today's dollars) value of your retirement fund. Due to inflation, $1,000,000 in 35 years will purchase significantly less than $1,000,000 today. The today's-dollars figure gives you a realistic sense of the purchasing power your savings will actually provide in retirement.

How much should I save for retirement?

A common target is to save 10 to 15 percent of your gross income for retirement, including any employer match. Another approach is to aim for 25 times your desired annual retirement income by the time you retire, which aligns with the 4% withdrawal rule. For example, if you want $60,000 per year in retirement, target a portfolio of $1,500,000.

What happens if I start saving later?

Starting later significantly reduces the power of compound growth. A person who starts saving $500 per month at age 25 will accumulate far more by age 65 than someone who starts saving $500 per month at age 40, even though the late starter contributes for only 10 fewer years. The early saver benefits from decades of additional compounding. Use the calculator to compare scenarios by changing the current age.

Should I factor in Social Security?

Social Security benefits can supplement your retirement savings but should not be your sole source of income. The average monthly Social Security benefit covers only a portion of most retirees' expenses. Use this calculator to determine how much you need from personal savings, then add expected Social Security benefits to estimate your total retirement income.