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Retirement planning, clearly explained.

Practical articles on Monte Carlo simulation, Social Security strategy, safe withdrawal rates, and building a retirement plan that actually works.

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Monte Carlo

What Is a Good Monte Carlo Success Rate for Retirement?

One couple, five plans. Retiring at 55 scores 51%, waiting to 65 scores 87%, and of the three standard fixes, the celebrated Social Security delay buys the fewest points.

July 3, 2026 · 8 min read Read →

RetirFi

Monte Carlo

Retirement Monte Carlo Analysis: How It Works and How to Read One

We entered one retired couple with $900,000 into the calculator and read every number it returned. The 97% success rate is only the headline.

July 1, 2026 · 5 min read Read →

RetirFi

Social Security

Social Security Spousal Benefits Explained

The non-working spouse is owed a check worth up to half the higher earner's. Entering it took the same $900,000 couple's plan from 47% to 96%.

June 30, 2026 · 6 min read Read →

All articles

Monte Carlo What Is a Good Monte Carlo Success Rate for Retirement? One couple, five plans. Retiring at 55 scores 51%, waiting to 65 scores 87%, and of the three standard fixes, the celebrated Social Security delay buys the fewest points. Jul 3, 2026 · 8 min Monte Carlo Retirement Monte Carlo Analysis: How It Works and How to Read One We entered one retired couple with $900,000 into the calculator and read every number it returned. The 97% success rate is only the headline. Jul 1, 2026 · 5 min Social Security Social Security Spousal Benefits Explained The non-working spouse is owed a check worth up to half the higher earner's. Entering it took the same $900,000 couple's plan from 47% to 96%. Jun 30, 2026 · 6 min Withdrawal Strategy How Required Minimum Distributions Affect Your Retirement Plan A retired couple with $1.2 million in a 401(k) faces two decades of forced, taxed withdrawals from 75. Converting to Roth in the low-income years before then comes out about $1 million ahead by 95. Jun 29, 2026 · 6 min Retirement Planning How Long Will $1 Million Last in Retirement? One retiree, $1 million, three spending levels. At $40,000 a year the money outlasts age 95 in every simulated run; at $80,000 it survives in about 1 in 5. Jun 27, 2026 · 9 min Monte Carlo Sequence of Returns Risk in Retirement A straight-line projection says the plan reaches 95 with nearly $1.9 million. Monte Carlo says 12 sequences in 100 still run dry. Sequence risk is the gap between those answers. Jun 24, 2026 · 5 min Social Security How Is Social Security Taxed in Retirement? The same $1 million retiree owes tax on Social Security every year when it sits in a 401(k), and nothing once half is in a Roth. Combined income is the lever. Jun 21, 2026 · 8 min Social Security Social Security Break-Even Age: Claiming at 62 vs. 67 vs. 70 Break-even arithmetic says the bigger checks catch up near 80. Five thousand Monte Carlo runs on the same $750,000 plan price the real choice: 85% success claiming at 62, 94% at 70. Jun 20, 2026 · 6 min Tax Strategy Roth vs. Traditional: Which Wins in Retirement? The choice is a bet on your tax rate now versus in retirement. RetirFi's Contribution and Conversion calculators price the bet with your own numbers. Jun 18, 2026 · 5 min Early Retirement The 4% Rule and Early Retirement: One Plan, Run at 65 and at 45 We entered the same $1.2 million plan into our calculator twice, retiring at 65 and at 45. The 4% rule scores 98% at 65 and 85% at 45, and 3.0% wins it back. Jun 18, 2026 · 5 min Retirement Planning How Much Do I Need to Retire? The 25x rule says $1.5 million. The subtract-Social-Security shortcut says $750,000. Five thousand Monte Carlo runs put the real number in between, at $1.2 million. Jun 16, 2026 · 6 min Withdrawal Strategy What Is a Safe Withdrawal Rate? The 4% Rule Explained A 4% withdrawal on $1 million survives 64 of 100 tax-aware simulations on its own. One average Social Security check takes the identical plan to 100%. Jun 6, 2026 · 5 min

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