Your result
What your result means
Saving $600 a month on top of $50,000, with a 6% average return, grows to about $1,034,029 by age 67 — $469,212 in today’s money after 2.5% yearly inflation. Withdrawing 4% of that in the first year would provide roughly $18,768 a year ($1,564 a month) before taxes and Social Security.
The math
Formula and sources
Balance = S × (1 + i)^n + C × ((1 + i)^n − 1) ÷ i Today’s dollars = Balance ÷ (1 + inflation)^years First-year income = today’s-dollar balance × withdrawal rate
- S
- current savings
- C
- monthly contribution
- i
- annual return ÷ 12
- n
- months until retirement
Returns are assumed constant and contributions flat; real markets vary year to year. The withdrawal rate is a planning convention, not a guarantee.
Sources we checked this against
- 1FV function (future value formula and examples)Microsoft Support · support.microsoft.com
- 2Compound Interest Calculator and explanationU.S. Securities and Exchange Commission, Investor.gov · investor.gov
- 3Retirement Savings (tax-advantaged accounts)U.S. Securities and Exchange Commission, Investor.gov · investor.gov
Formula last checked 2026-11-04. Found an error? Tell us and we will fix it.
Step by step
Two worked examples
Start at 25
Total contributions
$252,000
- Current age
- 25
- Retirement age
- 67
- Current retirement savings
- $0
- Monthly contribution
- $500
- Expected annual return
- 6%
- Expected inflation
- 2.5%
- Withdrawal rate in retirement
- 4%
42 years of $500 deposits ($252,000 in total) grow to $1,135,080, or $402,369 in today’s dollars.
Start at 40, same deposit
Total contributions
$162,000
- Current age
- 40
- Retirement age
- 67
- Current retirement savings
- $0
- Monthly contribution
- $500
- Expected annual return
- 6%
- Expected inflation
- 2.5%
- Withdrawal rate in retirement
- 4%
Waiting 15 years cuts contributions to $162,000 but the balance to only $403,273 — compounding needs time more than money.
| Result | Example 1 | Example 2 |
|---|---|---|
| Total contributions | $252,000 | $162,000 |
| Balance at retirement | $1,135,080 | $403,273 |
| In today’s dollars | $402,369 | $207,040 |
| Yearly income (today’s dollars) | $16,095 | $8,282 |
Questions
Frequently asked questions
What return should I assume?
Many planners test a range, such as 4% to 7% a year for a diversified portfolio before inflation. Try a lower number to see a cautious scenario.
What is the 4% rule?
It is a rule of thumb from historical U.S. market studies: withdrawing about 4% of savings in the first year, then adjusting for inflation, has historically lasted about 30 years. It is not guaranteed.
Does this include Social Security?
No. Add your estimated benefit from your Social Security statement (ssa.gov/myaccount) to the income figure.
Are taxes included?
No. Withdrawals from traditional 401(k)s and IRAs are taxed as income; qualified Roth withdrawals are not.