Sustainable Spending
Estimate the capital required to fund an inflation-adjusted, pre-tax portfolio withdrawal every year through age 120. The model tests one consistent spending obligation across thousands of reproducible market paths.
The Critical Needs Framework
Define the obligation, test it consistently, then separate required capital from potential surplus.
Enter Pre-Tax Withdrawals
Enter the amount the portfolio must distribute in year one. Include any taxes that the withdrawal itself must cover.
Test Through Age 120
The same 5,000 seeded return paths support every confidence target and chart. Spending rises at a fixed 2.5% annual inflation assumption.
Compare With Total Wealth
The result is an illustrative reserve target. A personalized plan can then account for Social Security, pensions, taxes, fees, and changing spending.
A Deliberately Conservative Horizon
This public illustration does not predict death or blend legacy balances into living-spending paths. Every scenario funds the entered withdrawal through age 120, so the fan chart and capital targets answer the same question.
5,000
Seeded return paths
2.5%
Fixed annual inflation
Age 120
Common terminal age
Critical Needs Simulator
Find the starting capital that supports your selected pre-tax withdrawals through age 120.
Your Inputs
Changing an input clears the prior scenario.
Pre-tax scope: the engine does not estimate federal or state tax. Enter the full portfolio distribution needed to cover both lifestyle spending and any tax paid from the withdrawal.
How Altar Rock Can Help
A planning analysis can replace the public assumptions with your actual cash flows, taxes, account types, pensions, and legacy goals.
Cash-Flow Mapping
Separate recurring lifestyle needs, taxes, gifts, and one-time purchases instead of treating spending as one fixed number.
Portfolio-Specific Risk
Use your holdings, fees, account tax character, and rebalancing policy in the return analysis.
Ongoing Monitoring
Revisit required capital as markets, spending, and family priorities change.
Legacy Coordination
Evaluate potential surplus only after retirement and liquidity obligations are covered.
Explore More Calculators
Model different strategies to build a comprehensive wealth transfer plan.
This deterministic-seed Monte Carlo illustration is educational and is not a guarantee or personalized financial plan. It assumes constant 2.5% inflation and stylized annual portfolio returns through age 120. It does not model mortality, taxes, investment fees, Social Security, pensions, cash-flow changes, or account-specific withdrawal rules. Actual required capital may differ materially. Altar Rock LLC is an SEC-registered investment adviser.