Free Mortgage Affordability Calculator
Estimate your monthly mortgage payment and total interest cost with our free online mortgage calculator. Enter the home price, down payment, loan term, and interest rate to instantly see your estimated monthly principal and interest payment. Understanding your mortgage costs before you buy helps you determine how much house you can actually afford, compare loan offers side by side, and plan your finances confidently. The calculator uses standard amortization math — the same formula banks and mortgage lenders use. A 30-year fixed mortgage at a lower interest rate results in smaller monthly payments but far more total interest paid over the life of the loan compared to a 15-year term. Use this tool to run scenarios: try different down payment amounts, compare 15-year vs 30-year terms, or see how a rate difference of 0.5% affects your total cost. Note: actual mortgage payments will also include property taxes, homeowner's insurance, and possibly PMI — these are not included in this estimate.
How to Use
- Enter your annual household income.
- Add your monthly debt payments (car loans, student loans, credit cards).
- Set your down payment percentage and interest rate.
- Choose between a 15-year or 30-year loan term.
- Enter property tax rate, annual insurance, and HOA fees if applicable.
- View your maximum affordable home price, monthly payment breakdown, and DTI ratio instantly.
FAQ
- What does the mortgage calculator include?
- This calculator computes principal and interest only — the two core components of any mortgage payment. Real monthly housing costs are typically higher because they also include property taxes (which vary by location), homeowner's insurance (typically $100–200/month), and private mortgage insurance (PMI) if your down payment is less than 20%. Add these estimates to get your full PITI (Principal, Interest, Taxes, Insurance) payment.
- How much should I put as a down payment?
- A 20% down payment eliminates PMI and gives you the best loan terms, but it's not always required. Many conventional loans allow as little as 3–5% down, FHA loans allow 3.5%, and VA loans for veterans allow 0% down. However, smaller down payments mean higher monthly payments, more total interest paid, and PMI costs until you reach 20% equity. Try different down payment amounts in the calculator to see the tradeoffs.
- What is the difference between a 15-year and 30-year mortgage?
- A 30-year mortgage has lower monthly payments but you pay significantly more total interest — often double or more compared to a 15-year mortgage. A 15-year mortgage has higher monthly payments but builds equity faster and dramatically reduces total interest cost. For example, on a $300,000 mortgage at 7%, a 30-year term costs about $418,000 in total interest; a 15-year term at 6.5% costs only about $170,000 — a savings of nearly $250,000.
- How does my credit score affect my mortgage rate?
- Your credit score is one of the most important factors in determining your mortgage interest rate. Borrowers with scores above 760 typically qualify for the best rates. Each step down — from 760 to 720, 720 to 680, and so on — generally adds 0.25%–0.5% to your rate. On a $300,000 mortgage over 30 years, a 1% higher rate increases your total interest paid by approximately $60,000. Improving your credit score before applying can be one of the highest-return financial moves you can make.