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.
A strong foundation, propelled by community...
From real estate and ACA optimization to Roth conversions and the Bucket Strategy - explore everything FIREproof can model.
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.
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.
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.
Bucket Strategy
A market-aware three-bucket withdrawal strategy. Pauses growth-bucket sales during bear markets, refills aggressively in good ones.
Cash Flow Priorities
Tell the simulator exactly where surplus income should go each year. Max out a 401k, build a target balance, or split by percentage - drag-and-drop the order.
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.
About Me
Lauren Boland
Founder & Software EngineerLong-time FIRE enthusiast. Numbers nerd. Compound interest is her friend.
"One of my favorite simulators is cFIREsim.com"
"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."
"We for sure nerded out for hours on cFIREsim for our first WPF Long Weekend retreat."
"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."
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.