House Affordability Calculator
As a quick rule of thumb, most lenders cap your monthly housing payment at 28% of your gross monthly income and your total monthly debt at 36% (the 28/36 rule). On a $90,000 household income, that works out to roughly $2,100 a month for housing before taxes and insurance are added. Your exact number depends on your down payment, interest rate, existing debt, and loan term — which is exactly what the calculator above solves for.
How the House Affordability Calculator Works
This tool takes your annual income, monthly debts, available down payment, interest rate, and target debt-to-income ratio, then works backward to the maximum home price a lender would typically approve. It isn’t guessing — it’s running the same math a loan officer runs, just before you ever submit an application.
The calculation has three layers. First, it finds your maximum allowable monthly payment based on the ratio you set. Second, it subtracts your existing debts and estimated property tax and insurance from that ceiling. Third, it converts the remaining amount into a loan size using your interest rate and term, then adds back your down payment to get a purchase price.
Understanding the 28/36 Rule
The “28” is your front-end ratio — housing costs alone (principal, interest, taxes, insurance) divided by gross income. The “36” is your back-end ratio — that same housing cost plus every other monthly debt: car loans, student loans, credit cards, and child support. Conventional lenders generally want to see 36% or below, though some approve up to 43-45% with strong credit or a larger down payment. FHA loans are typically more flexible on this ratio than conventional financing.
If you already have significant monthly debt, your back-end ratio will bind before your front-end ratio does. That’s worth checking directly with the Debt-to-Income Ratio Calculator, which shows both ratios side by side using your actual numbers rather than the calculator’s default assumptions.
Why Your Down Payment Changes More Than the Purchase Price
A larger down payment does three things at once: it lowers your loan amount, it can eliminate private mortgage insurance once you cross 20% equity, and it often qualifies you for a better interest rate. Because affordability is driven by monthly payment, not sale price, a 20% down payment versus a 5% down payment on the same monthly budget can mean a meaningfully higher purchase price. Run your own down payment scenarios in the Down Payment Calculator to see exactly how much that gap is worth in your situation.
The Monthly Payment Is More Than Principal and Interest
This is where many first-time buyers underestimate their budget. A mortgage payment has up to five components, often abbreviated PITI plus HOA:
- Principal — the portion that pays down your loan balance
- Interest — the lender’s charge for the loan
- Taxes — property tax, billed annually but usually collected monthly through escrow
- Insurance — homeowner’s insurance, and PMI if your down payment is under 20%
- HOA dues — if the property is part of an association
Property tax rates alone vary from under 0.5% to over 2% of home value depending on the state, which can shift your true monthly cost by hundreds of dollars on an identical purchase price. Once you have a target price from this calculator, run it through the full Mortgage Calculator to see the complete monthly breakdown, including taxes and insurance, not just principal and interest.
First-Time Buyers: FHA and VA Options
If you’re putting down less than 10%, it’s worth comparing government-backed loan programs before assuming conventional financing is your only path. FHA loans allow down payments as low as 3.5% with more flexible credit requirements, calculated in detail in the FHA Loan Calculator. If you’re a veteran or active-duty service member, the VA Mortgage Calculator models loans that often require no down payment at all and carry no PMI, which changes the affordability math significantly.
Should You Buy at All Right Now?
Affordability isn’t only about qualifying for a loan — it’s also about whether buying beats renting in your specific market and timeline. If you expect to move within two to three years, transaction costs (closing costs plus agent commission on resale) can outweigh the equity you build. The Rent vs. Buy Calculator compares both paths using your actual rent, expected appreciation, and how long you plan to stay, rather than a generic rule of thumb.
Building the Rest of Your Budget
Once you know your target price range, it helps to see how a future mortgage payment fits alongside everything else you spend each month. The Budget Calculator breaks down a full monthly budget by category, so you can confirm the number this calculator gives you is one you can actually live with — not just one a lender would approve.
Frequently Asked Questions
How much house can I afford on a $70,000 salary?
Using the 28% rule, that’s roughly $1,630 a month in gross income terms for housing, before other debts are counted. Depending on your down payment, interest rate, and existing debt, that typically supports a purchase price in the $220,000–$260,000 range at current interest rates — enter your own numbers above for an exact figure.
Is the 28/36 rule still accurate in 2026?
It remains the standard most conventional lenders reference, though many now approve back-end ratios up to 43-45% for borrowers with strong credit scores or larger down payments. Government-backed loans like FHA can go higher still.
Does this calculator include closing costs?
No — this tool estimates the ongoing monthly affordability of a purchase price. Closing costs are a separate, one-time cash requirement, typically 2-5% of the purchase price, and should be budgeted for in addition to your down payment.
What credit score do I need to get the best affordability?
Credit score doesn’t change this calculator’s math directly, but it strongly influences the interest rate a lender will offer you — and interest rate is one of the biggest levers on how much home your monthly budget supports. A lower rate on the same monthly payment translates directly into a higher affordable purchase price.
Should I use my gross income or take-home pay?
Use gross (pre-tax) income. That’s the figure lenders use when calculating your debt-to-income ratio, even though it will feel higher than the number that actually lands in your bank account.