Home Affordability Calculator

Suppose you earn $90,000 a year ($7,500 gross per month), pay $500/month toward a car and student loans, and have $40,000 saved for a down payment. The 28% rule caps your housing payment at $2,100, while the 36% rule allows $2,700 for all debt − with $500 already committed, that leaves $2,200 for housing. The lower of the two, $2,100, is your housing budget. After roughly $300 for property tax and $150 for insurance, about $1,650 is left for principal and interest − which at 6.5% over 30 years supports a loan near $261,000. Add the $40,000 down payment and you can afford a home around $300,000. This home affordability calculator runs that whole chain for your numbers in one click, and once you settle on a price you can drop it into the mortgage calculator to see the full monthly payment.

The formula behind the answer

Affordability is driven by the 28/36 rule. Your maximum monthly housing payment is:

From that budget we subtract estimated monthly property tax and home insurance to find how much is left for principal & interest. The maximum loan is then the P&I budget divided by the standard amortization factor, and your maximum home price is simply loan + down payment. Because property tax scales with the home price, the calculator solves for the price iteratively so the numbers stay consistent.

Front-end vs back-end DTI

Lenders look at two debt-to-income ratios. The front-end ratio is your housing payment alone divided by gross monthly income − the "28" in 28/36. The back-end ratio adds every other monthly debt (car, student, credit card minimums, child support) on top of the housing payment − the "36." If you carry significant debt, the back-end ratio usually becomes the binding constraint, which is why paying down a loan before you buy can raise your borrowing power more than a small raise would.

Gross income, not take-home

DTI uses gross (pre-tax) income, so a payment that passes the 28/36 test can still strain your budget once taxes, retirement contributions, health premiums and everyday spending come out. Many buyers deliberately target a payment below the maximum − treating the calculator's result as a ceiling, not a goal − to leave room for maintenance, emergencies and rising property taxes.

How to afford more house

• Pay down debt: every $100/month of debt removed frees up roughly the same in housing budget under the 36% rule.
• Save a larger down payment: it adds directly to your maximum price and can eliminate PMI at 20% down − the down payment calculator helps you set a savings target.
• Shop the rate: a lower interest rate means more of your payment buys home, not interest.
• Consider a longer term: a 30-year loan lowers the monthly payment versus 15 years, raising the price you qualify for (at the cost of more total interest).

How to use this calculator

You only need a few numbers to get a realistic ceiling on your home price. Work through the fields in order:

1. Annual or monthly income: enter your gross (pre-tax) pay. If two people are buying together, combine both incomes that the lender will count.
2. Monthly debts: add the minimum payments on car loans, student loans, personal loans, credit cards, and any court-ordered alimony or child support. Leave out rent, utilities, and groceries.
3. Down payment: type the cash you have saved. It is added on top of the loan your budget supports to give your maximum price.
4. Interest rate & term: use a current quoted rate (or a recent national average for your credit tier) and pick 30, 20, or 15 years.
5. Property tax & insurance: enter your local annual figures, or accept the estimates. These are subtracted from your housing budget before the loan is calculated.

The result updates instantly. Read the maximum home price at the top, then check the front-end and back-end DTI to see which limit is holding you back.

Who this calculator is for

This tool turns your paycheck into a realistic price ceiling, so it helps anyone deciding where to start their search:

• First-time buyers who want a target price range before they tour homes or talk to a lender.
• Couples combining two incomes and several debts who need to see the net effect on borrowing power.
• People paying down debt who want to see how much more house they could afford after a loan is gone.
• Move-up buyers checking whether a larger home fits the budget once the current mortgage is added in.
• Anyone curious whether a listing they like is realistically within reach on their income.

A second worked example: high debt, same income

Take the same $7,500 gross monthly income, but now you carry $1,200/month in debt (a newer car plus larger student loans). The 28% rule still allows $2,100 for housing, but the 36% rule leaves only $2,700 − $1,200 = $1,500. The lower figure, $1,500, becomes your housing budget − so the back-end ratio is now the binding limit. After about $250 for tax and $130 for insurance, roughly $1,120 remains for principal and interest, supporting a loan near $177,000. With the same $40,000 down, your maximum price falls to about $217,000 − roughly $80,000 less than the low-debt buyer earning the exact same salary. This is the single clearest illustration of why lenders weigh the back-end ratio so heavily.

Key terms explained

• Gross monthly income: your total pay before taxes and deductions, divided by 12. Lenders use this, not your take-home pay, for DTI.
• Front-end ratio: the proposed housing payment as a percentage of gross monthly income − the "28" in 28/36.
• Back-end ratio: all monthly debt payments, including the new mortgage, as a percentage of gross monthly income − the "36."
• Principal & interest (P&I): the part of your housing payment that actually repays the loan, after tax and insurance are set aside.
• Down payment: the cash you put in up front. It is not borrowed, so it adds directly to the price you can afford.
• Pre-approval: a lender's conditional commitment based on verified income, credit, and assets − stronger than this estimate, which is a planning figure only.

What changes the result the most

If you adjust the inputs and watch the maximum price move, a few factors dominate:

• Income: the biggest lever − both DTI limits scale directly with gross monthly income.
• Existing debt: every dollar of monthly debt comes straight out of the back-end budget and can flip the binding constraint from the 28% to the 36% rule.
• Interest rate: a higher rate means more of each payment is interest, so the same budget supports a smaller loan.
• Down payment: adds directly to the price and, at 20%, removes PMI from the real-world payment.
• Property tax rate: varies by county from under 0.4% to over 2% of value, so local rates can shift your price meaningfully.

Limitations and assumptions

This calculator is a planning estimate, not a pre-approval. Keep these assumptions in mind:

• It applies a generic 28/36 rule; real programs differ − FHA loans, for example, often allow higher ratios, and lenders add their own overlays.
• It does not include PMI, HOA dues, or closing costs, all of which reduce the price you can comfortably afford.
• It uses gross income, so it does not reflect how taxes, retirement contributions, and everyday spending affect your real cash flow.
• It assumes your credit and assets qualify you for the rate you enter; a lower score usually means a higher rate and a smaller budget.
• Property tax and insurance are treated as level, but both typically rise over time.

A third worked example: the down-payment lever

Down payment does two jobs at once, and it is the lever buyers most often underestimate. Return to the low-debt buyer earning $7,500 gross a month with $500 in monthly debt, whose 28% rule sets a $2,100 housing budget and a principal-and-interest budget near $1,650. At 6.5% over 30 years that P&I supports a loan of roughly $261,000. With $40,000 down the maximum price is about $301,000; bump the savings to $80,000 and the price ceiling jumps to about $341,000 − the extra $40,000 of cash translates dollar-for-dollar into price, on top of the loan your income already supports. Crossing the 20% threshold does something the budget math does not show directly: it removes private mortgage insurance from the real-world payment, freeing part of your housing budget that would otherwise go to PMI. That is why a buyer who is close to 20% often gains more by saving a little extra than by stretching the interest-rate assumptions, and why pairing this tool with the down payment calculator gives a fuller picture than either one alone.

How DTI limits differ by loan program

The 28/36 rule is a conventional rule of thumb, not a universal cap. Different loan programs apply different debt-to-income ceilings, and knowing where yours sits explains why a lender might approve more − or less − than this calculator's generic estimate:

• Conventional loans: often target a back-end ratio around 36%, but with strong compensating factors (high credit, large reserves, a sizable down payment) many will stretch toward 43% to 45%.
• FHA loans: government-backed and built for lower down payments, FHA frequently allows back-end ratios in the 43% to 50% range when other parts of the file are strong, which can push the affordable price above a plain 28/36 estimate.
• VA loans: for eligible veterans and service members, VA leans on a residual-income test in addition to DTI, so qualifying borrowers can sometimes carry higher ratios than the 36% baseline.
• USDA loans: for eligible rural and suburban buyers, USDA typically uses ratios near 29/41, again differing from the generic 28/36.

Because this calculator applies a single 28/36 rule, treat its number as a conservative middle-of-the-road estimate. A program that allows a higher back-end ratio will usually raise the price you qualify for, while lender overlays (a lender's own stricter rules layered on top of program minimums) can pull it back down. Your debt-to-income ratio on its own is the single number that most directly decides which programs and ratios are open to you.

Tips to make the estimate more accurate

A few habits turn a rough ceiling into a number you can plan around with confidence:

• Use a real, recent rate. Interest rates move week to week. Pull a current quote for your credit tier and loan type rather than an old figure − a half-point difference visibly changes the price you qualify for.
• Look up your county's property tax rate. Effective rates run from under 0.4% to over 2% of value depending on location, and tax is subtracted from your housing budget before the loan is calculated, so a national average can be off by hundreds of dollars a month.
• Capture every recurring debt. Missing a single car or student-loan payment understates your back-end ratio and inflates the result. Pull a recent credit report so nothing is left out.
• Add a buffer for PMI and HOA. The estimate stops at tax and insurance. If you expect to put down under 20% or buy in a community with dues, shave the result so the real payment still fits.
• Stress-test against take-home pay. Because DTI uses gross income, run the resulting payment against your actual paycheck and savings goals before treating it as affordable.

Run the numbers a few different ways − with and without a debt paid off, at a slightly higher rate, with a larger down payment − and you will quickly see which lever moves your price the most for your situation.

Affordability vs. monthly payment: a quick comparison

It is easy to confuse "how much house can I afford" with "what will my payment be," but they are opposite directions of the same math. This affordability calculator starts from your income and debts and works backward to a maximum price. The mortgage calculator starts from a known price and works forward to a monthly payment. In practice you use them together: get a ceiling here, pick a target price comfortably below it, then confirm the full PITI payment on the mortgage page. If that payment feels too high even though the price is "affordable" on paper, lower the target − the affordability ceiling is the most a lender allows, not the figure that protects your monthly budget.

How it compares to related calculators

This page answers "how much house can I afford on my income?" If you have a different question, a sister tool fits better:

• Once you have a target price, use the Mortgage Calculator to see the full monthly payment with taxes, insurance, and PMI.
• To plan how much cash to save up front, use the Down Payment Calculator.
• To check your debt-to-income ratio on its own, use the Debt-to-Income Calculator.
• To compare loan terms or see the principal-and-interest figure directly, use the Mortgage Payment Calculator.
• Still weighing whether to buy at all, use the Rent vs. Buy Calculator to compare the long-run cost of renting against owning.
• To see how aggressive extra payments could clear the loan early, use the Mortgage Payoff Calculator.