How to use this calculator
Enter your gross annual household income, your monthly recurring debts (car loans, student loans, minimum credit card payments, child support — anything that shows up on your credit report), and the cash you have available for down payment. The calculator runs your debt-to-income ratio against typical lender thresholds and works backward from a qualifying monthly payment to a maximum purchase price. Adjust the interest rate to match what you've been quoted (or current market rates), and tweak the property-tax and insurance assumptions if you have specific local data. The output gives you both a maximum purchase price and a recommended price — the recommended figure backs off the absolute maximum to leave room for emergency reserves and lifestyle costs after closing. Most borrowers find their actual comfort range sits below their maximum approval. Use the calculator to set a realistic shopping ceiling before touring homes, not after.
How the math works
Affordability math reverses the standard payment formula. Lenders typically allow a maximum total debt-to-income ratio of 43% (some programs up to 50% with strong compensating factors). Maximum monthly housing payment = (gross monthly income × DTI cap) − existing monthly debts. From there, the calculator solves for the loan amount that produces that payment given the rate and term: Loan = Payment × (1 − (1 + r)^−n) ÷ r, then adds your down payment to get maximum purchase price. Worked example structure: a household earning $9,000/month gross with a 43% DTI cap has $3,870/month available for total debt service. Subtract $600 in existing car and credit-card payments to get $3,270 available for housing. Allocate roughly $300 of that to taxes and insurance, leaving the remainder for principal and interest. The calculator solves for the supportable loan amount given current rates (pulled from the mortgage rates page) and adds your down payment to produce the maximum purchase price. The recommended figure runs about 90% of that ceiling to preserve cash-flow margin after closing.
When to use this vs the others
Use this calculator at the start of your home search to set a price ceiling that matches your real qualifying capacity. Once you've narrowed to a specific home, the mortgage payment calculator gives you the exact monthly PITI for that property. If you're early in the process and not sure if buying makes sense at all relative to your current rent, the rent vs buy calculator answers that broader question. For VA borrowers, the VA entitlement calculator confirms whether your no-down purchase power covers your target price.
Frequently asked questions
What DTI ratio does this calculator use?
By default, 43% — the standard upper limit for qualified mortgages and typical conventional underwriting. You can adjust the slider to match your situation. Many programs allow higher (FHA up to 57%, VA effectively higher via residual income), but qualifying at the upper edge of DTI usually means a payment that's uncomfortable in practice.
Should I buy at my maximum approval amount?
Almost never. Lenders qualify you on a snapshot of income and debts, but life adds expenses — kids, car repairs, retirement contributions, emergencies — that don't show up on a mortgage application. Most financial advisors recommend buying at 70–80% of your maximum approval to keep monthly housing comfortable.
Does the calculator account for closing costs?
Yes — it reserves a portion of your stated cash for closing costs (typically 2–5% of purchase price). If you're working with seller concessions or lender credits, you'll have more cash available for down payment than the default assumes; adjust the closing-cost slider accordingly.
How does mortgage insurance affect affordability?
Mortgage insurance is a real monthly cost that subtracts from your housing budget. With less than 20% down on conventional, expect $50–$300/month in PMI depending on credit. FHA monthly MIP can run $80–$300+. VA has no monthly MI. The calculator factors in program-typical MI costs when you select a loan program.
Why is my recommended price below the maximum?
The maximum is what you can technically qualify for. The recommended price (~90% of max) preserves margin for surprises — closing-cost overruns, unexpected repairs in the first year, mortgage rate variability if you haven't locked. Buying at the recommended figure leaves room without leaving money on the table.