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Monte Carlo Calculator
Run simulations to estimate outcome probabilities.
Read the Monte Carlo guideSuccess Rate
0%
Chance of reaching your target balance.
Median Outcome
$0
5th Percentile
$0
95th Percentile
$0
How this calculator works
Monte Carlo runs thousands of market scenarios to estimate the probability of reaching your target balance.
Key assumptions
- Annual returns are modeled with a normal distribution.
- Contributions occur once per year.
- Volatility represents typical market swings.
Example
Example: $100,000 starting balance, $12,000 annual contribution, 7% return, 12% volatility. The calculator shows success rate and percentile outcomes.
FAQs
- What is volatility? It measures how much returns vary year to year.
- Is a 90% success rate enough? It depends on your risk tolerance—higher is safer.
- Why are results different each run? Simulations are randomized; small differences are normal.
Sources: CFPB • Federal Reserve • IRS
Last updated: 2026-02-04