Mortgage Calculator
Estimate Your Monthly Home Loan Payment
Direct Answer: How is a monthly mortgage payment calculated?
A monthly mortgage payment is calculated based on the Principal (home price minus down payment), the Interest Rate, and the Loan Term (typically 15 or 30 years). It covers both raw loan repayment and interest costs, which amortize over time.
Total Loan Payoff Breakdown (Principal vs Interest)
15-Year vs. 30-Year Mortgage Comparison
Choosing between a 15-year and a 30-year mortgage has a massive impact on both your monthly cash flow and your long-term wealth. Below is a standard comparison of how the structures differ under the hood:
| Mortgage Parameter | 30-Year Fixed Term | 15-Year Fixed Term |
|---|---|---|
| Monthly Payment | Lower (more affordable monthly cash flow) | Higher (typically 30-40% higher P&I) |
| Interest Rates | Standard market rate | Lower (often 0.5% to 1.0% discount) |
| Equity Accumulation | Slow (very little principal paid in early years) | Very Fast (accelerated wealth building) |
| Total Lifetime Interest | High (easily 2-3x the original principal) | Extremely Low (saves tens of thousands) |
How Mortgage Payments Work
A mortgage is a loan used to purchase real estate. When you take out a mortgage, you agree to repay the borrowed amount (principal) plus interest over a fixed period, typically 15 or 30 years. Each monthly payment covers both interest on the remaining balance and a portion of the principal.
In the early years of a mortgage, most of your payment goes toward interest. As you pay down the principal, the interest portion decreases and more of your payment goes toward building equity in your home. This is called amortization.
The Formula
This calculator uses the standard amortization formula:
Where:
- M = Monthly payment
- P = Principal (home price minus down payment)
- r = Monthly interest rate (annual rate ÷ 12)
- n = Total number of payments (years × 12)
Tips for Getting a Better Mortgage
- Improve your credit score — A score above 740 qualifies you for the best rates. Pay down existing debt and fix any errors on your credit report before applying.
- Save for 20% down — This eliminates PMI and reduces your monthly payment significantly. Even 15% down can help negotiate better terms.
- Compare at least 3 lenders — Rates and fees vary widely between banks, credit unions, and online lenders. Getting three quotes can save you thousands.
- Consider a 15-year term — Monthly payments are higher, but you'll pay dramatically less interest over the life of the loan and build equity faster.
- Lock your rate — Once you find a good rate, lock it in. Rate locks typically last 30-60 days and protect you from market fluctuations during closing.
Frequently Asked Questions
What is included in a monthly mortgage payment?
A typical monthly mortgage payment includes principal (the loan amount you're paying down), interest (the cost of borrowing), property taxes, and homeowners insurance. This is often called PITI. Our calculator shows the principal and interest portion. Your actual payment will be higher once you add taxes and insurance.
What is a good interest rate for a mortgage in 2025?
As of early 2025, average 30-year fixed mortgage rates hover between 6% and 7.5%. A 'good' rate depends on your credit score, down payment, loan type, and market conditions. Borrowers with excellent credit (740+) and 20% down typically qualify for the best rates.
How much house can I afford?
A common rule of thumb is that your monthly housing costs should not exceed 28% of your gross monthly income. So if you earn $6,000/month before taxes, aim for a total housing payment (including taxes and insurance) under $1,680. Use this calculator to work backward from your budget.
Should I make a 20% down payment?
A 20% down payment eliminates the need for Private Mortgage Insurance (PMI), which typically costs 0.5% to 1.5% of the loan amount per year. However, many loan programs allow 3% to 5% down. The tradeoff is a higher monthly payment and PMI until you reach 20% equity.
Does this calculator include property taxes and insurance?
No. This calculator shows principal and interest (P&I) only. Your actual monthly payment will include property taxes (varies by location, typically 0.5% to 2.5% of home value per year) and homeowners insurance (~$100-$300/month). Add these to your P&I for a complete picture.