Probability of Ruin Calculator
Free probability of ruin calculator runs Monte Carlo simulation for constant withdrawal retirement to output ruin probability, success and safe withdrawal rate.
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How It Works
Enter the inputs described in each field label for Probability of Ruin Calculator. The calculator validates basic constraints such as positive denominators where required and shows clear outputs when data is incomplete. Pull figures from the same reporting period when combining balance sheet and income statement items.
Probability of ruin estimates the chance a portfolio depletes before the planning horizon under lognormal return assumptions. Review summary metrics, breakdown tables, and interpretation bands updated on every keystroke. Compare scenarios by adjusting one assumption at a time to see sensitivity. Use Monte Carlo FIRE, SWR Dynamism, and Sequence of Returns on portfolios.tools for retirement withdrawal research.
Use Monte Carlo FIRE, SWR Dynamism, and Sequence of Returns on portfolios.tools for retirement withdrawal research.
Use Probability of Ruin Calculator whenever inputs change: after market moves, new contributions, or revised personal assumptions. Bookmark the page for quick reruns without installing software.
Step by step
- Open Probability of Ruin Calculator and enter your current inputs.
- Review calculated outputs and summary tables.
- Adjust assumptions and compare scenarios side by side.
Worked example
Enter the sample inputs described in How it works to reproduce the scenario step by step for probability of ruin calculator.
Adjust one input at a time to see sensitivity. Probability of Ruin Calculator updates instantly so you can stress test optimistic and conservative assumptions before acting.
When to use this calculator
Reach for Probability of Ruin Calculator when you need quick what if analysis before trades, allocation changes, or plan updates.
Pair with related tools when the decision spans taxes, liquidity, or multi year projections beyond what one formula captures.
Common mistakes
Copying outputs without checking input units or stale market prices is a frequent error with Probability of Ruin Calculator. Confirm tickers, percentages, and dates before acting.
Running a single baseline scenario ignores tail risks. Stress test with conservative inputs and compare against related tools listed below when the decision is material.
The Formula
Each year: Portfolio = (Portfolio − Withdrawal) × (1 + Return)
Ruin if Portfolio ≤ 0 before horizon ends
Uses fixed nominal withdrawals without inflation adjustment. Sequence of returns risk dominates real world outcomes.
Limitations and assumptions
Uses fixed nominal withdrawals without inflation adjustment. Sequence of returns risk dominates real world outcomes. Probability of Ruin Calculator does not replace personalized advice. Fees, slippage, account specific rules, and behavioral constraints may change real world outcomes.
Key terms
- What does Probability of Ruin Calculator measure
- Probability of ruin estimates the chance a portfolio depletes before the planning horizon under lognormal return assumptions.
- How is the formula applied
- The formula block on this page shows every intermediate step so you can audit the math against textbook definitions.
- Model assumption
- Interpret results in context rather than as automatic buy, sell, or accept signals.
Compare alternatives
Use Monte Carlo FIRE, SWR Dynamism, and Sequence of Returns on portfolios. Use those calculators when probability of ruin calculator alone does not capture the full decision.
Internal links on portfolios.tools help you chain calculators: run Probability of Ruin Calculator first, then validate edge cases with a specialized tool from the related section below.
FAQ
What does Probability of Ruin Calculator measure?
Probability of ruin estimates the chance a portfolio depletes before the planning horizon under lognormal return assumptions. This calculator runs entirely in your browser on portfolios.tools. Enter your assumptions in the form above and review outputs instantly without sending data to any server. Students use it for homework checks, analysts for quick sanity tests, and planners for scenario analysis before building spreadsheet models. Results depend on input quality: stale data or optimistic assumptions can mislead even when the math is correct. Always reconcile outputs with source documents and professional judgment when decisions have material consequences.
How is the formula applied in Probability of Ruin Calculator?
The formula block on this page shows every intermediate step so you can audit the math against textbook definitions. Uses fixed nominal withdrawals without inflation adjustment. Sequence of returns risk dominates real world outcomes. Match input units to the formula: percentages as whole numbers unless labels specify decimals, currency in one consistent denomination, and time periods aligned across numerators and denominators.
How should I interpret Probability of Ruin Calculator results?
Interpret results in context rather than as automatic buy, sell, or accept signals. Probability of ruin estimates the chance a portfolio depletes before the planning horizon under lognormal return assumptions. Pair this tool with related calculators on portfolios.tools when your decision spans taxes, liquidity, covenants, or multi year projections that one ratio cannot capture alone.
What are common input mistakes with Probability of Ruin Calculator?
Common mistakes include mixing annual and quarterly figures, ignoring non recurring items, and treating point estimates as certainty. Stress test with conservative and optimistic inputs before acting. Document assumptions when sharing outputs with colleagues or clients.
What are the limitations of Probability of Ruin Calculator?
Limitations include simplified models that omit sector nuance, regulatory changes, and behavioral factors. Uses fixed nominal withdrawals without inflation adjustment. Sequence of returns risk dominates real world outcomes. This page provides educational math only, not personalized investment, tax, or legal advice.
How do I use this probability of ruin calculator on a phone or tablet?
Yes. Probability of Ruin Calculator runs entirely in your mobile browser with the same formulas as desktop. Optional localStorage may remember inputs on your device when enabled in browser settings.
Where is my data stored when I use Probability of Ruin Calculator?
Nowhere on our servers. Calculations execute locally in your browser. Optional localStorage saves form fields on your device only and never transmits portfolio numbers over the network.
Should I rely on Probability of Ruin Calculator for tax or legal decisions?
No. Probability of Ruin Calculator provides educational math only. Tax law, account rules, and personal circumstances vary. Consult a qualified tax or legal professional before transactions with material consequences.
Related Tools
Use Monte Carlo FIRE, SWR Dynamism, and Sequence of Returns on portfolios.tools for retirement withdrawal research.