FREE · US RETIREMENT PLANNER · 2026 DATA
10,000 futures.One honest plan.
The retirement calculator that factors in your spouse, your kids, and reality — not just a cheerful average. Runs 10,000-path Monte Carlo with 2026 Social Security, Medicare, and inflation data built in.
Data sources
LIVE EXAMPLE · COUPLE AGE 45 · $380K SAVED
10,000 simulations
Y-axis scaled to median path’s peak. Some simulated paths extend above the visible range — see the percentile table for the full distribution.
median $2.3M · 10th pct $890K · depletion age 91
Real Monte Carlo — not a single “average” answer.
Not just averages.
10,000 simulated futures show the probability of success — and the shape of the tail.
Your spouse and kids, modeled.
Dual earners, dependent care, and legacy impact — not a single-person average.
Specific shortfall fixes.
"Contribute $340 more/month OR retire 14 months later" — not vague warnings.
WHY THIS WORKS
Built on the same math the brokerages use, made honest about uncertainty.
Vanguard, Fidelity, and Schwab all run Monte Carlo simulations to model retirement uncertainty. Yearfold uses the same methodology — 10,000-path historical bootstrap from 1928–2025 market data — but makes the assumptions visible and the output specific. Every number on this site traces to a primary source. Every plan is shareable via URL. The math is open; only the implementation is ours.
BUILT ON THE BEST PUBLIC DATA
Same methodology as the major brokerages — radically more transparent.
Yearfold runs the same Monte Carlo methodology you’ll find in Vanguard, Fidelity, Schwab, ProjectionLab, and Boldin — but with every assumption, every data source, and every result published. Most calculators don’t show their work. We do. See how Yearfold compares
METHODOLOGY
10,000-path Monte Carlo, 1928–2025 historical bootstrap
MARKET DATA
Robert Shiller / Yale online data
INFLATION
U.S. Bureau of Labor Statistics CPI-U
SOCIAL SECURITY
Social Security Administration 2026
HEALTHCARE & TAXES
CMS 2026 Medicare + IRS contribution limits
RECENT FROM THE BLOG
Field notes on real retirement math.
July 15, 2026
The 2027 Social Security COLA Forecast Just Fell a Full Point. This Is Why You Plan for a Range.
June CPI cut the leading 2027 Social Security COLA forecasts a full point to about 3.6–3.8%. Why the estimate keeps whipsawing — and how to plan for a range, not a guess.
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July 8, 2026
The $6,000 senior deduction: what it actually does (and doesn't do)
No, Social Security is not tax-free now. Here's what the OBBBA senior deduction really is: $6,000 per person 65+, phasing out above $75,000/$150,000 MAGI, gone after 2028 — with worked examples and the Roth-conversion trap nobody mentions.
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July 1, 2026
Social Security's 2032 deadline: what a 22% benefit cut would do to your plan
The June 2026 Trustees Report moved the retirement trust fund's depletion date up to late 2032 — after which only 78% of scheduled benefits are payable. Here's what a 22% cut means in dollars, why claiming at 62 is usually the wrong reaction, and how to model the cut in your own plan.
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