FIRE Projections & Retirement Modeling

The FIRE (Financial Independence / Retire Early) modeling landscape is mostly free. cFIREsim and FIRECalc are the canonical historical-Monte-Carlo simulators; ProjectionLab is the modern paid tool that's worth its sub for serious planning; Engaging Data has the best free interactive visualizations. Bogleheads + Mad Fientist + ChooseFI are the canonical free education. For Bogleheads / FI education see Bogleheads & FI Education; for portfolio see Ghostfolio; for the budget side see Actual Budget; for the broader index see Self-Hosted Personal Apps; for inheritance / tax see Inheritance & Tax Planning; for tax software see Free Tax Software.

Free historical-Monte-Carlo simulators

• ★ cFIREsim — free; community-maintained; historical sequence-of-returns simulation; configurable spending, asset allocation, Social Security, pension, withdrawal-strategy variants. The most-popular free FIRE simulator.
  • https://www.cfiresim.com/
• ★ FIRECalc — free; the original; less polished UI than cFIREsim; same underlying historical-data approach.
  • https://www.firecalc.com/
• Portfolio Visualizer — free + paid; backtesting, Monte Carlo, factor regression; deeper than the dedicated FIRE tools.
• Personal Capital / Empower retirement planner — free; basic Monte Carlo; aggregator-tied.
• NewRetirement (PlannerPlus) — free + paid; rich tax modeling; popular with FIRE crowd.
• Boldin (formerly NewRetirement) — recent rebrand; free + paid.

Engaging Data (free interactive)

• ★ Engaging Data — free; the best free interactive FIRE / retirement visualizations; "When can I retire?" + "Rich, broke, or dead?" + asset-decumulation calculators. Concise, beautiful, no upsell.
  • https://engaging-data.com/

ProjectionLab (★ paid, worth it)

• ★ ProjectionLab — paid (~$120/yr) + limited free trial; modern modern modern interactive FIRE planner; multiple scenarios, side-by-side comparisons, deterministic + Monte Carlo, deep tax modeling, what-if interactive sliders. The 2025–26 power-user pick.
  • https://projectionlab.com/

Spreadsheet-driven (free + flexible)

• ★ Mad Fientist's tax-optimized spreadsheets — free; downloadable templates.
• ★ Bogleheads "Variable Percentage Withdrawal" — free spreadsheet; alternative to 4% rule.
• ★ vertex42 retirement templates — free Google Sheets / Excel.
• Budget-shape templates — adapt for FIRE projection.

Education / community (★ ★)

• ★ ★ ★ Bogleheads forum + wiki — free; the deepest free personal-finance community on the internet; FIRE-curious or otherwise. See Bogleheads & FI Education.
• ★ Mr Money Mustache blog — free; the canonical FIRE blog (2011–); foundational reading.
• ★ Mad Fientist — free; tax-strategy-flavored FIRE; Roth-conversion-ladder math, mega-backdoor, HSA hacks.
• ★ ChooseFI podcast + community — free podcast; large free community.
• Afford Anything (Paula Pant) — free podcast.
• Earn & Invest (Doc G) — free podcast.
• The Money Guy Show — free podcast.

Books (paid)

• ★ The Simple Path to Wealth (JL Collins) — paid; the FIRE bible; stock-series origin.
• ★ Your Money or Your Life (Vicki Robin & Joe Dominguez) — paid; the original FI text from 1992.
• A Random Walk Down Wall Street (Burton Malkiel) — paid; passive-investing classic.
• The Bogleheads' Guide to Investing — paid; ★ the canonical Boglehead three-fund text.
• Early Retirement Extreme (Jacob Lund Fisker) — paid; the radical-frugality companion to MMM.
• Quit Like a Millionaire (Kristy Shen) — paid; geographic-arbitrage angle.
• Die With Zero (Bill Perkins) — paid; the "FIRE has a balance problem" rejoinder.

Withdrawal strategies (★ understand these)

• ★ 4% Rule (SWR — safe withdrawal rate) — Trinity Study; 4% inflation-adjusted from a 60/40 portfolio survives ~30 years 95%+ of historical sequences.
• Variable Percentage Withdrawal (VPW) — Bogleheads; adjusts withdrawal each year by remaining balance × age-adjusted percentage; never runs out.
• Guyton-Klinger guardrails — adjust spending up/down based on portfolio performance.
• Bond tent / glidepath — increase bonds 5–10 years before retirement, then decrease again — addresses sequence-of-returns risk.
• Bucket strategy — short-term cash + medium-term bonds + long-term stocks; sleep-well-at-night-flavored.
• Roth conversion ladder — convert traditional → Roth in low-income early-retirement years; access in 5 years tax/penalty-free; the canonical FIRE tax move.
• 72(t) SEPP — substantially-equal periodic payments for pre-59½ access without penalty; rigid; less flexible than the Roth ladder.

Health insurance bridge (★ the pre-Medicare problem)

• ★ ACA marketplace — subsidies are based on MAGI; FIRE'd low-MAGI households often get heavily subsidized health insurance.
• ★ Roth conversions reduce ACA subsidies — model the tradeoff.
• ★ HSA — the FIRE crowd's favorite triple-tax-advantaged account; contribute through working years, save receipts, reimburse decades later.
• COBRA — bridge for 18 months after leaving employer.
• Healthcare-sharing ministries — cheaper but not insurance; risk asymmetric.

Geographic / international

• Geographic arbitrage — FIRE'ing in lower-cost-of-living locales.
• International tax — FEIE, FTC; complicated. Talk to a tax advisor before relocating.
• Healthcare comparison — many countries' systems are cheaper + better than US private; some require residency.

License / pricing

• cFIREsim, FIRECalc, Engaging Data, Mad Fientist resources, Bogleheads, MMM, ChooseFI, vertex42: free.
• ProjectionLab: paid (~$120/yr) + free tier.
• Boldin / NewRetirement: free + paid.
• Portfolio Visualizer: free + paid.
• Personal Capital / Empower: free.
• Books: paid (cheap used / library free).

Pick this if…

• Default free FIRE simulation: cFIREsim + Engaging Data visualizations.
• Want the polished modern paid tool: ProjectionLab.
• Want deep tax modeling: Boldin / NewRetirement PlannerPlus.
• Want education before tools: Bogleheads wiki + JL Collins's stock series + Mad Fientist.
• Want a podcast routine: ChooseFI.
• Want the radical frugality version: Mr Money Mustache + ERE.
• Want the "spend more" rejoinder: Die With Zero.
• Roth-conversion-ladder math: Mad Fientist's tax articles + cFIREsim modeling.