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PROBABILITY MODELING TOOL

Monte Carlo Portfolio Simulator

Markets don't move in straight lines. Run hundreds of simulations to see the full range of where your portfolio could end up.

Every line on the chart is a possible future. Adjust return, volatility, and time horizon to see how the probabilities shift.

No sign-up required · Instant results

Ages

Portfolio

Starting Balance$500,000
Monthly Contribution$2,000

While working

Returns & Risk

Pre-Retirement Return7%

Growth while working

Post-Retirement Return5%

More conservative in retirement

Annual Volatility15%

Diversified portfolio: 12-18%

Retirement Spending

Monthly Withdrawal$4,000

$48,000/year from portfolio

Simulations

1,000 simulations · Ages 45-90

Portfolio Growth & Retirement Scenarios

P90 zone
P75 zone
Median
P25 zone
P10 zone

Retirement Timeline

How long your savings may last — median simulation

Age 45Age 65Age 90
Accumulation
Funded
Accumulation: 20 yrs
Funded: 25 yrs
Fully funded to Age 90

At Retirement

$0

median at age 65

Plan Success Rate

0%Probability ofsuccess

Below minimum

70%80%90%

Min: 70% · Target: 80%+ · Ideal: 90%+

Success = money remaining at age 90. Failure = portfolio runs out before then.

Great Scenario

$0

90th pct, age 90

Tough Scenario

$0

10th pct, age 90

Course Correction Needed

Significant Shortfall

Only 0% of simulations survive to age 90. At $4,000/month, you need $684,240 at retirement. The median projection is $0, a gap of $684,240.

Projected at Retirement
$0
Goal Requirement
$684,240
Funding Gap
$-684,240

Confidence Meter

ShortfallBuffer0%funded

Projected vs. goal requirement

Across 1,000 simulations, the median run sustains your portfolio through age 90. The next question is whether you can spend more, give more, or retire earlier without breaking the plan.

This is an estimate, not a number to plan around alone.

This calculator is an educational tool to help you think through scenarios. The results are illustrative estimates based on the inputs you provided and general assumptions. They are not financial advice, and the numbers shown should not be relied on as exact to your situation.

Real outcomes depend on factors a calculator can't fully model: your complete tax picture, plan-specific rules, market performance, IRS rate changes, life events, and how all the pieces of your financial life interact. Past performance does not guarantee future results.

Before making any decision based on these numbers, let's talk. I'll look at your full picture, pressure-test the assumptions, and help you understand what these numbers actually mean for you, at no cost.

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