Calculator Inputs
yrs
Your age today.
yrs
The age at which you plan to retire.
$
Total retirement savings today (401k, IRA, brokerage, etc.).
$
How much you invest toward retirement each month.
%
Assumed average annual portfolio return. S&P 500 historical: ~10% nominal, ~7% real.
%
Long-run inflation rate. US historical average: ~3%. Fed target: 2%.
$
Estimated monthly spending in today's dollars. Calculator adjusts for inflation.
%
Safe withdrawal rate per year. The classic '4% rule' is a common benchmark.
yrs
How many years your portfolio needs to last in retirement.
⚠ Shortfall of $1.84M — you need $2,024/mo to reach the required corpus
Results
Projected Savings
$2.38M
At age 65
Required Corpus (4% rule)
$4.22M
25× annual expenses (inflation-adj.)
Est. Monthly Retirement Income
$12,543
Sustainable for 25 yrs
Inflation-Adj. Monthly Expenses
$14,069
In today's dollars, at age 65
Surplus / Shortfall
-$1.84M
Years to Retirement
35 years
Savings Projection vs Required Corpus
Return Rate Scenarios
Your projected savings under pessimistic, base, and optimistic return assumptions.
| Scenario | Annual Return | Projected Savings | Required Corpus | Gap / Surplus | On Track? |
|---|---|---|---|---|---|
| Pessimistic | 5.00% | $1.42M | $4.22M | -$2.80M | ✗ No |
| Base | 7.00% | $2.38M | $4.22M | -$1.84M | ✗ No |
| Optimistic | 9.00% | $4.09M | $4.22M | -$125,840 | ✗ No |
Savings Growth by Age
| Age | Year | Projected Savings | Total Contributed | Investment Gains |
|---|---|---|---|---|
| 35 | 2031 | $142,474 | $110,000 | $32,474 |
| 40 | 2036 | $273,568 | $170,000 | $103,568 |
| 45 | 2041 | $459,410 | $230,000 | $229,410 |
| 50 | 2046 | $722,864 | $290,000 | $432,864 |
| 55 | 2051 | $1.10M | $350,000 | $746,343 |
| 60 | 2056 | $1.63M | $410,000 | $1.22M |
| 65 | 2061 | $2.38M | $470,000 | $1.91M |
The 4% Rule
The 4% rule (Bengen Rule) states you can safely withdraw 4% of your portfolio in year one, then adjust for inflation each year, with a historically very low probability of running out of money over 30 years. A required corpus of 25× annual expenses follows directly: 1 / 0.04 = 25.
Real Return vs Nominal Return
Nominal return is what your portfolio earns before inflation. Real return = nominal − inflation. At 7% nominal and 3% inflation, your real return is 4%. This calculator uses nominal return during accumulation and real return during retirement income estimation.
Why Monthly Contributions Matter More Than Return
For most investors in accumulation phase, contribution rate dominates. Doubling your monthly contribution from $500 to $1,000 has more impact than increasing your expected return from 7% to 10% — especially in the first 15 years. Control what you can control, and use a dollar-cost averaging calculator to see how consistent monthly investing compounds over your specific timeline.
Retirement Income Shortfalls
If your projected savings fall short, the main levers are: (1) increase monthly contributions, (2) retire later, (3) reduce planned retirement spending, or (4) take on slightly more equity exposure to improve expected returns. Social Security is not modeled here — add it to your monthly income estimate.
Frequently Asked Questions
What is the 4% rule for retirement?
The 4% rule (from the Trinity Study) states that retirees can withdraw 4% of their portfolio in the first year, then adjust for inflation each year, with a high probability of the portfolio lasting 30+ years. This means you need a portfolio roughly 25x your annual expenses to retire safely.
How much do I need to retire?
Using the 4% rule, you need 25 times your annual expenses. For $5,000/month in expenses ($60,000/year), you need $1.5 million. This planner calculates your specific required corpus after adjusting your expenses for inflation to the year you plan to retire.
What return rate should I use for retirement planning?
A conservative pre-retirement return is 6–7% (real, after inflation) for a diversified stock/bond portfolio. More aggressive all-stock portfolios target 7–8% real. This planner lets you set the nominal return and inflation rate separately and runs pessimistic and optimistic scenarios.
What is the FIRE number?
The FIRE (Financial Independence, Retire Early) number is 25x your annual expenses — the portfolio size needed to sustain indefinite withdrawals at a 4% rate. Some FIRE adherents use 33x (3% withdrawal rate) for extra safety margin, especially when retiring in their 30s or 40s with a longer expected time horizon.
How much should I have saved for retirement by age 30, 40, or 50?
Common industry rules of thumb suggest roughly 1x your annual salary saved by 30, 3x by 40, and 6x by 50, though the right number depends heavily on your planned retirement age, expenses, and other income sources. These are rough benchmarks, not guarantees — use this calculator's inputs for a projection specific to your situation.
Does this retirement calculator include Social Security?
No, this calculator's monthly income estimate is based only on your projected investment portfolio and does not factor in Social Security or pension income. If you expect Social Security benefits, add your estimated monthly benefit on top of the calculator's income figure to get a more complete picture.
* This calculator is for educational purposes only and does not constitute financial advice. Results assume constant returns and inflation, which will vary in practice. Consult a certified financial planner for personalized retirement planning.
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