Before you start scrolling Zillow at midnight, run the numbers. A mortgage calculator is the fastest way to get honest about what you can afford.
What the calculator tells you
Our monthly payment calculator estimates your payment based on:
- Home price (or loan amount)
- Down payment
- Interest rate (we auto-fill this week's average)
- Loan term (usually 30 years)
It shows principal and interest only. Your real housing payment will be higher once you add property taxes, insurance, and possibly PMI.
The 28/36 rule
Most lenders use this as a sanity check:
- 28% — your housing payment shouldn't exceed 28% of gross monthly income.
- 36% — your total debt payments shouldn't exceed 36% of gross monthly income.
So if you earn $8,000/month before tax, your max housing payment is around $2,240.
The costs the calculator doesn't show
- Property taxes: roughly 1–2% of home value per year.
- Homeowners insurance: $1,000–$2,000+ per year.
- PMI: 0.5–1% per year if your down payment is under 20%.
- HOA fees: varies by community — sometimes brutal.
- Maintenance: budget about 1% of home value per year.
How down payment changes the picture
On a $400,000 home at 7%:
- 5% down ($20,000): ~$2,529/mo + PMI
- 10% down ($40,000): ~$2,395/mo + PMI
- 20% down ($80,000): ~$2,128/mo (no PMI)
A bigger down payment shrinks the loan, kills PMI, and often unlocks a better rate.
Try it
Plug your numbers into the calculator on the homepage. Move the home price, down payment, and term around until you find a payment you can live with — not the maximum a lender will let you take.
This calculator gives estimates only. Talk to a mortgage professional for advice based on your actual finances.