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Monte Carlo Retirement Calculator

Will your money last through retirement?

Explore 1,000 possible market futures with Monte Carlo simulation. Start with a few numbers, then add detail at your own pace.

See how your savings could last across possible market futures.

Example projection · Investments

Monte Carlo investment projection from age 45 to 90Median final balance $1.8M. Poor-outcome final balance $538.5K. Shading: 10th–90th percentile. The lower-end balance at each age (10th percentile). Outcomes can be worse. This is not a guaranteed minimum or one continuous simulated life.$0$3.5MAge 45Age 90
MedianPoor outcomes (10th)
Shading: middle 80% of simulated outcomes.
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Example plan

An example to explore. Replace these numbers with yours.

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MONTE CARLO · 1,000 SCENARIOS

How often does your money last?

96.6%

of simulated futures succeed through age 90.

Nominal balances · inflation off

Monte Carlo investment projection from age 45 to 90. Median final balance $1.8M. Poor-outcome final balance, 10th percentile, $538.5K. Not a guaranteed minimum.$0$1.8M$3.5MRetire · 65Age 45Age 68Age 90At age 90Median ━$1.8MPoor outcomes (10th) ┄$538.5K

Shaded range: 10th–90th percentile

How this is calculated

The lower-end balance at each age (10th percentile). Outcomes can be worse. This is not a guaranteed minimum or one continuous simulated life.

Monte Carlo explores simulated market years, not a prediction. A successful run funds the modeled expenses and finishes with money remaining. Taxes and account access restrictions are not modeled.

Balances are nominal; inflation is not applied. Review the assumptions before relying on the result.

Play your retirement plan

An interactive game: live one possible future and make decisions along the way.

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Explore individual simulation paths

Use Classic layout · Same saved plan

A Free FI Calculator That Shows Real Probabilities

Most retirement calculators give you a single number based on average returns. This financial independence calculator runs 1,000 market scenarios to show the full range of outcomes, so you can plan for uncertainty instead of ignoring it.

Used by the FIRE community. Free, no signup required.

Learn About the Methodology