How much house can you actually afford?
At the current 30-year fixed rate of 6.66%, a household earning $100,000 with $500 of monthly debt payments and 20% down can support a home of about $360,424 under the conventional 28/36 rule — roughly $50,276 below the current U.S. median sale price of $410,700. Put your own numbers in below.
Most affordability calculators answer a slightly different question than the one you are asking — they tell you the largest loan a lender would approve, which is not the same as the largest loan you should sign. This one shows both ratios, tells you which of the two is actually binding on your file, and separates the payment a lender counts from the money you will genuinely spend on the house each month. The full derivation is written out below the tool, along with everything it does not account for.
Home affordability calculator
Your finances
Before tax. Lenders qualify on gross income, not take-home.
Car loans, student loans, credit-card minimums, child support.
Effective U.S. rates run roughly 0.3% to 2.2% by state.
Maximum home price
$360,424
20% down at 6.66% over 30 years
Down payment
$72,085
20% of the price
Loan amount
$288,339
Housing payment
$2,333
What the lender counts
With maintenance
$2,634
What you'll actually spend
Which rule is holding you back
- Front-end cap (28% of gross)
- $2,333/mo
- Back-end cap (36% of gross, minus $500 of debt)
- $2,500/mo
- Binding housing budget
- $2,333/mo
Your income is the constraint. The 28% housing rule bites before the total-debt rule does, which means clearing more debt will not raise this number — a larger down payment, a lower rate, or a cheaper tax jurisdiction will.
Inside the limit you selected.
The 28/36 rule, written out
Conventional underwriting applies two debt-to-income ratios at the same time, and your budget is whichever one runs out first. Both are measured against gross monthly income — pay before tax, before retirement contributions, before health insurance. That is deliberate on the lender’s part and worth remembering, because it means a payment that fits comfortably inside the 28% rule can still be a large share of what actually lands in your account.
gross monthly income G = annual income ÷ 12 FRONT-END (28%) housing payment ≤ 0.28 × G BACK-END (36%) housing payment + other debts ≤ 0.36 × G housing budget H = min( 0.28 × G , 0.36 × G − other debts )
“Housing payment” here means principal, interest, property tax, homeowner’s insurance and mortgage insurance — the components a lender escrows or counts. It does not include maintenance, utilities or HOA-adjacent costs the lender ignores but you cannot.
Turning a budget into a price
This is the step most calculators fudge. You cannot just subtract tax and insurance from the budget and run the remainder through the amortisation formula, because property tax and PMI are both functions of the price you are trying to find. They have to be collected on the same side of the equation and solved for together:
k = i(1 + i)ⁿ ÷ [ (1 + i)ⁿ − 1 ] monthly P&I per $1 of loan i = rate ÷ 100 ÷ 12, n = 360 H = V(1−d)k + V·t/12 + INS/12 + V(1−d)·pmi/12 H − INS/12 V = ───────────────────────────────────── (1−d)k + t/12 + (1−d)·pmi/12 V = maximum purchase price d = down payment as a fraction t = annual property tax rate INS = annual insurance premium pmi = 0.005 per year, and only when d < 0.20
Insurance is the one flat dollar term, so it moves to the numerator; everything else scales with price and belongs in the denominator. The result is exact rather than approximate, which matters most where property taxes are extreme. Two identical households with identical budgets — one in a 0.4% tax county, one in a 2.2% county — do not differ by a few thousand dollars of buying power. At today’s rate the gap is well over 15% of purchase price.
Maintenance sits outside the qualifying math on purpose. A 1%-of-value annual reserve is the common planning figure and the calculator shows it as a separate line, because a lender will not count it against you and the house will not stop needing it.
A worked example at today’s rate
A household earning $100,000 a year with $500 a month in car and student-loan payments, putting 20% down, in a county with a 1.1% effective property tax rate and an $1,800 annual insurance premium. The rate is read live when this page is generated.
| Gross monthly income, G | $8,333 |
| Front-end cap, 28% of G | $2,333/mo |
| Back-end cap, 36% of G less $500 of debt | $2,500/mo |
| Binding housing budget, H | $2,333/mo |
| Rate | 6.66% |
| Payment factor, k (per $1 of loan) | 0.0064263 |
| Maximum purchase price, V | $360,424 |
| Down payment, 20% | $72,085 |
| Loan amount | $288,339 |
| Principal & interest | $1,853/mo |
| Property tax | $330/mo |
| Insurance | $150/mo |
| Total housing payment | $2,333/mo |
Rate: Freddie Mac via FRED, August 2026Median sale price: MSPUS, U.S. Census Bureau and HUD via FRED, Q2 2026. Published quarterly.
Notice which cap bound: the 28% front-end rule, at $2,333 a month, came in below the back-end cap of $2,500. This household is income-limited rather than debt-limited, so paying off the $500 of monthly obligations would not raise the ceiling at all. The rate and the down payment would.
Against the U.S. median sale price of $410,700 (Q2 2026), this household is about $50,276 short of the median home. That gap is the central fact of the current market: a six-figure household income with modest debt no longer clears the median purchase at prevailing rates in much of the country. It closes from three directions — a lower rate, a larger down payment, or a cheaper market.
What this assumes, and what it leaves out
Gross income, not take-home.
Both ratios are measured against pay before tax, retirement contributions and health premiums — that is how underwriting works, so that is how we model it. In a high-tax state a payment at exactly 28% of gross can be closer to 40% of what actually reaches your account. Run the resulting payment against your real net pay before deciding it is comfortable.
Only debts on your credit report count.
Car loans, student loans, credit-card minimums, personal loans and court-ordered payments go into the back-end ratio. Childcare, tuition, healthcare, alimony paid outside a court order, and supporting a family member do not — not because they are cheap, but because a debt-to-income calculation cannot see them. Add them yourself before trusting the ceiling.
Property tax and insurance are single numbers you set.
Effective property tax rates vary from roughly 0.3% to over 2.2% by state and change again between towns in the same county. Insurance premiums have moved by multiples in wind, wildfire and flood-exposed markets in recent years, and flood coverage is separate and not modelled at all. Both inputs are dominant in the price you can support — look up the real figures for the parcel.
HOA dues and special assessments are excluded.
Lenders do count HOA dues against your ratios, and this calculator does not have a field for them. If you are shopping condos or a planned community, subtract the monthly dues from the housing budget before reading the price.
PMI is modelled at a flat 0.5% of the loan per year.
Real premiums run roughly 0.3% to 1.5% and are priced jointly off credit score and loan-to-value. FHA loans work differently — an upfront premium plus an annual one that on most current loans runs for the life of the loan rather than cancelling at 78% of original value.
Closing costs, reserves and moving costs are not included.
Expect 2% to 5% of the purchase price in cash at closing on top of the down payment, plus a reserve. A buyer with exactly the down payment saved is not ready to close at this price.
The rate is a national survey average.
Freddie Mac surveys what lenders advertise for a well-qualified borrower with 20% down on a conforming loan. Your quote depends on credit tier, loan size, occupancy and points. It is the centre of a distribution, not a promise.
This is not a pre-approval.
It is arithmetic on numbers you typed. Only a lender pulling credit and verifying income and assets can tell you what you qualify for.
Common questions
What is the 28/36 rule?
Two limits applied at the same time. The front-end ratio says your total monthly housing payment — principal, interest, property tax, insurance and mortgage insurance — should not exceed 28% of your gross monthly income. The back-end ratio says that housing payment plus every other recurring monthly debt payment should not exceed 36% of gross monthly income. Whichever limit binds first is your real budget, and for most households carrying a car payment or student loans it is the back-end one. Many conforming lenders will stretch the back-end ratio to 43%, which is the Qualified Mortgage ceiling, and some government-backed programmes go higher with compensating factors. Qualifying at 43% and being comfortable at 43% are different questions.
How does this calculator work out the maximum price?
It solves the payment equation backwards. Property tax and mortgage insurance are both percentages of the price you are solving for, so they cannot simply be subtracted from the budget — they have to be moved to the same side of the equation. Writing the housing cap H as H = V(1−d)k + V·t/12 + INS/12 + PMI(V), where V is the price, d the down-payment fraction, k the monthly payment per dollar of loan, t the annual tax rate and INS the annual insurance premium, and rearranging for V gives an exact answer. The common shortcut — assume 60% of the budget is principal and interest — is much less accurate, because in a 2.2% property tax state the true share is nowhere near 60%.
Why is the number lower than what a lender told me I could borrow?
Lenders quote the maximum you qualify for, which is a different question from what you should spend. The gap usually comes from three places. First, the back-end ratio: a lender working to 43% or 50% will approve a far larger loan than this page shows at 36%. Second, maintenance: this calculator shows a 1%-of-value annual maintenance reserve separately because no lender escrows it, but the roof still fails. Third, everything not on a credit report — childcare, healthcare premiums, retirement contributions, tuition — none of which appears in a debt-to-income calculation at all.
What raises my budget fastest?
When the 28% housing rule binds before the total-debt rule, clearing more debt will not help — you have already run out of income, not headroom. From there the levers are a lower interest rate, which is largely determined by your credit tier; a larger down payment, which reduces both the loan and, past 20%, the mortgage insurance; and a lower-tax county, which can be worth tens of thousands of dollars of purchase price on the same monthly payment.
Does the calculator include closing costs and moving costs?
No. It sizes the monthly payment and the price that payment supports. Closing costs typically run 2% to 5% of the purchase price and are due in cash at the table on top of the down payment, so a buyer with exactly 20% saved and nothing else is not actually ready to close on this price. Budget the down payment, the closing costs, a moving allowance and a reserve of several months of the full payment before treating the number above as your ceiling.
Where to go next
The other two calculators
- Mortgage calculator — takes the price you landed on here and shows the full payment and amortisation schedule.
- Rent vs. buy calculator — whether buying at that price beats renting over the years you plan to stay.
How we get these numbers
- Methodology — every formula and assumption on the site.
- Data sources — each provider and how current it is.
- All markets — where your budget actually buys something.
Find a market that fits the number
A budget is only useful next to real prices. These city and state pages carry current values, inventory and days on market:
The rate in this calculation is set by your credit file
Half a point of rate moves this budget by tens of thousands of dollars. Tell us your timeline and we'll send exactly what to clear before you apply, and how long each item takes.