Frequently asked questions
Short answers, each backed by the documented model. For your own numbers, the planner re-runs the full simulation in your browser as you type.
How much house can I afford?
It depends on more than income: your savings, spending, taxes, mortgage rate, and how long until you want work to be optional. The Home Affordability Simulator answers with a probability instead of a rule of thumb — it simulates thousands of 30-year futures (market crashes, job losses, real taxes, the full cost of owning) and reports the highest purchase price where at least 85% of them still reach financial independence on your schedule. As a starting point, the how-much-house pages show that ceiling for salaries from $50K to $400K.
Is the 28% rule (or 3–4× salary) a good guide?
It's a lending guideline, not an affordability answer. Payment-to-income ratios can't see your savings rate, state taxes, market risk, or retirement timeline — two households the rule treats identically can have wildly different odds of staying on track. In this site's simulations, the sustainable salary multiple ranges from under 2× to over 6× depending on those factors.
What does this calculator model that others don't?
Correlated risk and the full carrying cost: market returns and home prices drawn together, job-loss probability that spikes in crashes, federal/FICA/state/capital-gains taxes across taxable, pre-tax, and Roth accounts, plus property tax, insurance, maintenance, PMI, and selling costs. It grades a purchase by whether you still reach financial independence by your target age — and it reports the specific futures that break the plan, not just the average.
What do 'Comfortable', 'Workable', and 'Risky' mean?
They are probability bands on reaching your financial-independence target by your target age: Comfortable means at least 85% of simulated futures make it, Workable at least 70%, Risky below that. A separate guardrail caps every recommendation at the price where forced sales (layoff plus downturn) stay under the ruin tolerance, 5% by default.
Is it free? What's the catch?
Free, no account, no paywall. The simulation runs entirely in your browser — there is no server-side processing and nothing you enter is transmitted, stored, or sold. The site may carry clearly disclosed sponsored links; they never affect the simulation.
How accurate is a Monte Carlo simulation?
It's honest about uncertainty rather than falsely precise. The model draws thousands of possible futures from stated assumptions (documented, with every known simplification, on the methodology page) and reports how often a plan survives them. The output is a probability under those assumptions — a much better decision input than a single projected number, but still a model: garbage assumptions in, garbage odds out. Every assumption is editable.
Should I rent or buy?
Usually the wrong first question. The interesting question is whether a specific purchase price keeps your plans intact in the futures where things go wrong — renting is simply what the money does otherwise, and the simulator prices both paths on identical market draws. A purchase that beats renting on average can still be the worse choice if it breaks in the bad 10% of futures.
Do state taxes really change what I can afford?
Yes, more than most people expect: state income tax comes out of exactly the money that has to outrun your mortgage — your annual investing surplus — and the drag compounds for decades. Across this site's state pages (all 50 states plus D.C., with 2025 statutory brackets), the same household's odds of retiring on time move by whole percentage points between no-tax and high-tax states, equivalent to tens of thousands of dollars of purchase-price headroom.
What interest rate, returns, and inflation does it assume?
Editable defaults, not hidden constants: a 6.25% thirty-year mortgage, 7% expected nominal portfolio return with 15% volatility, 3.5% home appreciation, 2.5% inflation, and a 35% stock-home correlation. Every one of them is an input you can change, and the methodology page explains where each default comes from.
Can I save or share a scenario?
Yes — the share button encodes the entire scenario into the URL itself (nothing is uploaded), so a link reopens the exact simulation for anyone. You can also export the full year-by-year percentile bands as CSV, or embed the quick-check widget on your own site with one iframe.
Keep going
- How much house each salary affords — the ceiling, computed per income tier.
- Can I afford a $X house on a $Y salary? — specific price-and-income verdicts.
- Affordability by state — all 50 states' 2025 tax treatment, simulated.
- Guides — the model's answers to the classic questions.