Enter your income, debts, and down payment to find the maximum home price you can afford under the 28/36 DTI rule.
How to Use the House Affordability Calculator
Fill in annual income, monthly debts, and the down payment you have available, then adjust the two DTI percentages and the estimated monthly tax-and-insurance figure if the defaults don't match your situation — everything recalculates as you type.
The 28% and 36% defaults aren't arbitrary; they're the "28/36 rule," a mortgage-industry convention that's guided conventional underwriting for decades — no more than 28% of gross monthly income going toward the house payment itself, and no more than 36% toward total debt once the mortgage is added to everything else you owe.
Max Housing Payment = min(Income × Front-End % , Income × Back-End % − Other Debts)
Max Loan = Max P&I Payment × [1 − (1 + r)⁻ⁿ] ÷ rTwo ratios rarely produce the same ceiling, so the calculator takes whichever is lower and flags it as the binding constraint — usually the back-end ratio for anyone carrying meaningful car or student loan payments, since that's the one those debts eat into directly.
Individual lenders bend these numbers all the time — some conventional and FHA programs qualify borrowers well past 36% back-end with compensating factors like a large down payment or excellent credit — so treat this as the traditional benchmark, not a hard cutoff every lender enforces.