Sustainable Monthly Income
$1,887.17
Retirement Calculator
All-in-one retirement readiness summary.
Projected Savings at Retirement
$357,529.87
Desired Monthly Income
$4,000.00
Monthly Surplus/(Gap)
-$2,112.83
Retirement-phase income assumes the balance keeps earning a fixed 4% annual return while being drawn down.
How to use the Retirement Calculator
The Retirement Calculator is free and runs entirely in your browser — no sign-up, and nothing you enter leaves your device. It opens pre-filled with a realistic example, so you can see how it works before replacing any figure with your own; the results update as you type. Press Calculate to refresh the result panel, or Reset to return to the example.
The inputs it asks for:
- Current Age — a number.
- Retirement Age — a number.
- Current Savings — a dollar amount.
- Monthly Contribution — a dollar amount.
- Pre-Retirement Return — a percentage (enter 6 for 6%).
- Life Expectancy — a number.
- Desired Monthly Income — a dollar amount.
The formula
An all-in-one readiness check. It grows your savings to retirement, then computes the level monthly income that would draw that balance down to zero over your retirement years, assuming it keeps earning a fixed 4% while you spend it:
Sustainable monthly = the payment that amortizes the nest egg over the retirement months at 4%/yr- Nest egg
- savings compounded at your pre-retirement return, plus contributions
- retirement months
- (life expectancy − retirement age) × 12
The drawdown uses a fixed 4% annual return through retirement — a planning assumption, not a promise. It fully depletes the balance by your life-expectancy age, so living longer than expected would exhaust it; build in a margin.
Worked example
Using the example values — Current Age 40, Retirement Age 65, Current Savings $20,000.00, Monthly Contribution $300.00, Pre-Retirement Return 7%, Life Expectancy 90, and 1 more — the Retirement Calculator returns a Projected Savings at Retirement of $357,529.87. It also reports Sustainable Monthly Income ($1,887.17), Desired Monthly Income ($4,000.00), Monthly Surplus/(Gap) (-$2,112.83).
Prefer your own numbers? Change any field above and this recomputes instantly.
Key terms
- Nest egg
- Projected savings at the moment you retire.
- Sustainable income
- The level withdrawal that empties the balance over your planning horizon.
- Drawdown
- Spending down accumulated savings during retirement.
- Life expectancy
- The age to which the plan funds income — outliving it is the risk.
Frequently asked questions
Why 4% in retirement?
It's a common, cautious planning return for a balanced retirement portfolio — an assumption you can't control precisely. A lower rate produces a safer, smaller sustainable income.
Does it leave anything behind?
No — it draws the balance to zero at your life-expectancy age. To leave an estate, or guard against a long life, target income below the sustainable figure.
How is this different from the Retirement Planner?
Similar inputs, different output: the planner compares your nest egg to a lump-sum need; this one turns the nest egg into a monthly income figure.