FIREproof

Explore many proofs.

Build your FIRE.

FIREproof enables you to model, plan, and visualize your retirement… and all that happens along the way.

A retirement planning tool from the creator of cFIREsim.com, a mainstay in the retirement calculator world and FIRE community.

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FIREproof ProofView. Success rate dial alongside main summary chart

A strong foundation, propelled by community...

From real estate and ACA optimization to Roth conversions and the Bucket Strategy - explore everything FIREproof can model.

Draw down your portfolio with Guyton-Klinger, VPW, CAPE, or Hebeler autopilot, all backtested against 150 years of market history. See every strategy.

TIPS Bond Ladder/Tent

Each rung pays a guaranteed, inflation-adjusted amount in a specific year, so you fund the first part of retirement from maturing bonds instead of selling stocks into a downturn. Protect yourself from sequence-of-returns risk, then let your equities ride.

TIPS Bond Ladder setup showing rungs maturing year-by-year with guaranteed inflation-adjusted payouts

ACA Healthcare & Premium Tax Credits

Auto-lookup marketplace premiums by ZIP. Project your subsidy each year and optimize withdrawals to maximize the Premium Tax Credit. Auto-ends at Medicare age.

ACA Healthcare screen

Roth Conversion Optimizer

Manual or optimizer-mode Roth conversions. See bracket room, model the 5-year rule, and compare lifetime tax with and without conversions.

Roth Optimizer

Bucket Strategy

A market-aware three-bucket withdrawal strategy. Pauses growth-bucket sales during bear markets, refills aggressively in good ones.

Bucket Strategy

Real Estate Modeling

Model homes you own and homes you'll buy. Track mortgages year-by-year, project appreciation, plan a future purchase, run rental cash flow with depreciation, and even model a 1031 exchange.

Real Estate Adjustment showing primary residence and rental property with cashflow metrics

Withdrawal Strategies

Choose how each year's spending is sourced, then see the reasoning explained year by year.

  • Sequence-risk defense. When the market falls far from its peak, spending shifts to the accounts you mark as safe, so a downturn early in retirement never forces you to sell stocks at a loss.
  • Rebalance via withdrawal. Spend from whichever asset class has drifted overweight. Your withdrawals do the rebalancing, so year-end trades realize fewer capital gains.
  • Guyton-Klinger. Classic guardrails: spending rises after good years and cuts back when your withdrawal rate drifts too high, with decision rules backtested against history.
  • Risk-Based Guardrails. Each year's spending is solved against a target chance of success, so you always know how much you can safely spend given the markets you have actually lived through.
  • VPW. Variable Percentage Withdrawal spends an age-based percentage that rises each year, deliberately drawing the portfolio down over your lifetime so you enjoy your money instead of leaving it behind.

Tax-Aware Simulation

Income tax, capital gains with cost basis, FICA, RMDs, and 72(t) SEPP. Every withdrawal is filtered through real tax rules.

Try It - No Account Needed

Explore the full simulator with a pre-built scenario. Same engine, same charts. Tweak retirement age, spending, and allocation in real time.

See it in action

A peek at the charts and outputs that make FIREproof different.

Rich, Broke, or Dead. Stacked-area mortality-weighted outcome chart Real Estate ledger. Year-by-year mortgage paydown, appreciation, and rental cash flow

"One of my favorite simulators is cFIREsim.com"

Mr Money Mustache

"The tool that you've built here is absolutely fantastic, really well researched, and tons of great data. Thank you so much for building it."

Bigger Pockets Money

"We for sure nerded out for hours on cFIREsim for our first WPF Long Weekend retreat."

womens personal finance

"If there was a list of heroes of the financial independence movement, I'd advocate for Lauren Boland being on that list... Lauren developed cFIREsim, one of the more powerful and popular retirement calculators among members of the FIRE community."

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Feature Roadmap

AI-assisted scenario builder Describe your situation in plain language ("I'm 42, want to retire at 55, own a rental in Denver...") and have an LLM translate it into a fully configured simulation you can refine.

Account aggregation / read-only sync Securely pull current balances from your financial institutions so your starting point is always up to date - no more manual entry every quarter.

Whole-portfolio Monte Carlo Today Monte Carlo runs per-asset. Expand it to the entire portfolio with correlated returns so success probabilities reflect real diversification effects.

Mobile companion app A native/PWA companion to check your plan, glance at success rates, and tweak quick what-ifs from your phone.

Add your own feature requests!