What is a retirement calculator?
A retirement calculator is a planning tool that projects how a current balance and regular contributions may grow over time. If you want to isolate investment compounding, our Compound Interest Calculator provides a focused growth comparison. This calculator uses the ages, savings, monthly contribution, investment-return assumption and inflation rate you enter to estimate a future retirement balance.
It also converts that future balance into approximate today's dollars and estimates a level monthly withdrawal over the retirement period you select. The result is meant to help you compare scenarios, not predict exactly what markets or your future spending will do.
How does the retirement calculator work?
The calculator first finds the number of months between your current age and retirement age. Your existing savings are compounded monthly, and each monthly contribution is added to the account and compounded for the remaining time.
The projected balance is then discounted by your inflation assumption to show an approximate present-value equivalent. Finally, the calculator uses your post-retirement return and retirement length to estimate a level monthly withdrawal that would mathematically draw the projected balance down over that period.
What formulas does the retirement calculator use?
The savings projection combines compound growth on the current balance with the future value of regular monthly contributions.
Here, r is the monthly investment-return assumption and n is the number of months until retirement. Inflation adjustment discounts the projected balance by the annual inflation rate over the years to retirement.
The general compounding concept is consistent with the educational tools published by Investor.gov.
How do you use this retirement calculator?
- Enter your current age and planned retirement age.
- Add your current retirement savings and monthly contribution.
- Enter an annual return assumption for the years before retirement.
- Add an inflation assumption so the future balance can also be shown in today's dollars.
- Choose how many retirement years to model and a post-retirement return assumption.
- Select Calculate Retirement and compare the projected balance, growth and estimated monthly draw.
Try more than one return or contribution scenario. A calculator is most useful when it helps you see how different assumptions change the outcome.
What do the retirement calculator results mean?
Projected savings at retirement is the estimated future account balance based on the entered growth and contribution assumptions. Today's-dollar value discounts that future amount for the inflation rate you entered, which can make long-term purchasing power easier to understand.
Total contributed includes the current starting balance plus the monthly contributions made before retirement. Estimated investment growth is the difference between that contributed amount and the projected future balance. The monthly draw is a mathematical level-withdrawal estimate over the retirement years entered.
Which assumptions can change a retirement projection?
Time, contribution amount and investment return have large effects because compounding works across many years. Inflation matters because a future dollar may buy less than a dollar today. The retirement-period return also changes the monthly withdrawal estimate because money remaining in the account is assumed to continue earning the entered rate.
Actual retirement planning may also involve Social Security, pensions, taxes, investment fees, health expenses, required minimum distributions and changing spending. If much of your retirement saving happens through work, compare the projection with our 401(k) Calculator. The Investor.gov retirement resources and the U.S. Department of Labor retirement-plan guide provide additional educational context.
What are the limitations of a retirement calculator?
No calculator can know future market returns, inflation, taxes or how long a person will live. A constant annual-return assumption also does not model sequence-of-returns risk—the effect of receiving strong or weak market returns at different times.
This tool does not automatically include Social Security, pension income, tax treatment, investment fees or changing contributions. It is best used to compare planning scenarios and understand the mathematics behind them.
Who should use this retirement calculator?
It can be useful for adults who want a quick estimate of how current savings and regular contributions may grow toward retirement. It can also help compare the effect of retiring earlier or later, changing monthly contributions, or testing different return and inflation assumptions.
For decisions involving taxes, investment selection, withdrawal strategy or an individual retirement plan, consider qualified financial and tax guidance in addition to calculator estimates. You can also browse the full Finance Calculators category for related planning tools.
Retirement Calculator FAQs
Sources and methodology
The calculator uses standard compound-growth and annuity mathematics. These public resources provide additional educational information about compounding and retirement planning.