Home Affordability Calculator

How lenders actually decide

Approval hinges largely on debt-to-income ratio. The front-end ratio compares your housing payment to gross monthly income; the back-end ratio compares all monthly debt obligations, housing included, to that same income. Conventional loans commonly allow a back-end ratio in the mid-forties, and some programs stretch further with strong compensating factors like reserves or credit. Everything else being equal, paying off a car loan can raise your buying power more than a small increase in down payment.

Qualifying and comfortable are different numbers

The ceiling a lender allows is not a recommendation. A back-end ratio in the high forties is approvable and can still leave you house-poor once you add maintenance, furnishing, commuting and the ordinary cost of living. I would rather help you buy comfortably at a number you barely notice each month than max out an approval and watch it strain everything else. Run the calculator at your approval ceiling, then run it again at a payment that would still feel fine if your income dipped for six months.

Cash to close is the other constraint

Down payment is only part of what you bring. Closing costs commonly run in the low single-digit percentages of the purchase price, and you will also need funds for inspection, appraisal and moving. This tool includes an estimate so the picture stays complete — and remember that seller concessions can cover a meaningful share of closing costs when the negotiation is structured well.

Common questions

What debt-to-income ratio do I need?

Many conventional approvals land in the mid-forties on the back-end ratio, with some programs allowing more. Lower is better and gives you more room to negotiate.

Do student loans count even if deferred?

Usually yes. Most programs use either the actual payment or a calculated percentage of the balance, even during deferment. Rules vary by loan program, so ask your lender about your specific situation.

Should I buy at the top of my approval?

Rarely. The approval is a ceiling, not a target. Leave room for maintenance, furnishings and life.

More calculators

• Mortgage Payment (PITI) — See your true monthly payment, not just principal and interest
• Rate Buydown & Points — Permanent points and 1-0, 1-1, 2-1, 3-2-1 temporary buydowns
• Rent vs. Buy — Break-even year and net position over time
• Seller Net Sheet — What you actually walk away with after costs and payoff
• Refinance Break-Even — Monthly savings, break-even month, and lifetime interest
• Investment Property ROI — Cash flow, cap rate, DSCR and total return with leverage

Want these numbers run on a real address? Schedule your strategy call →

Educational estimate only — not a loan approval, appraisal, or tax advice. Michael Rush is a licensed REALTOR® with Keller Williams Realty DTC, not a lender, CPA, or attorney. Equal Housing Opportunity.