How to Use PMI Calculator
The PMI Calculator gives you a clear picture of your total monthly housing cost when a down payment is below 20%.
- Home Price — Enter the purchase price of the property.
- Down Payment — Enter the dollar amount you plan to put down. The PMI Calculator automatically calculates your down payment percentage.
- Loan Term — Choose your mortgage length in years (commonly 15 or 30).
- Annual Interest Rate — Enter your expected mortgage interest rate as a percentage.
- Annual PMI Rate — Enter the PMI rate quoted by your lender, or leave the default 0.5% as an estimate.
The PMI Calculator instantly outputs your estimated monthly principal and interest payment, monthly PMI, total monthly housing cost, annual PMI expense, and loan amount. If your down payment is 20% or more, the PMI Calculator confirms no PMI is required.
Formula & Theory — PMI Calculator
The PMI Calculator applies standard mortgage and insurance math:
Loan Amount = Home Price − Down Payment
Down Payment % = (Down Payment / Home Price) × 100
Monthly Rate = Annual Interest Rate / 100 / 12
Num Payments = Loan Term (years) × 12
Monthly P&I = Loan Amount × [r(1+r)^n] / [(1+r)^n − 1]
where r = Monthly Rate, n = Num Payments
Monthly PMI = Loan Amount × (Annual PMI Rate / 100) / 12
Annual PMI = Monthly PMI × 12
Total Monthly = Monthly P&I + Monthly PMI
| Symbol | Meaning |
|---|---|
| r | Monthly interest rate (annual rate ÷ 12) |
| n | Total number of monthly payments |
| P&I | Principal and interest portion of monthly payment |
When Does PMI Apply?
The PMI Calculator applies PMI whenever your down payment percentage is below 20%. Once you cross the 20% equity threshold — either through your down payment or by paying down principal — most lenders are required by law to cancel PMI automatically.
Use Cases for PMI Calculator
The PMI Calculator is an essential tool for anyone navigating the home-buying process:
- First-time home buyers — Understand the full monthly cost of homeownership before making an offer, including the PMI added by the PMI Calculator.
- Down payment planning — Use the PMI Calculator to model different down payment amounts and see how close you are to eliminating PMI entirely.
- Affordability analysis — Compare monthly costs across different home prices and interest rate scenarios with the PMI Calculator to stay within your budget.
- Refinancing decisions — If you have built equity, run the numbers through the PMI Calculator to estimate savings from dropping PMI after a refinance.
- Lender comparison — Different lenders offer different PMI rates. Plug each quoted rate into the PMI Calculator to compare total monthly costs side by side.
- FHA vs. conventional loans — FHA loans carry mortgage insurance regardless of down payment. Use the PMI Calculator to compare conventional loan PMI scenarios against FHA insurance premiums.
Disclaimer: Results from the PMI Calculator are estimates for informational purposes only. Actual costs depend on your lender, credit profile, loan type, and local regulations. Consult a licensed mortgage professional before making financial decisions.