Calculation details
Planning estimate only, not financial, tax, or legal advice. Verify assumptions and current rules before making decisions.
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What does this calculator estimate?
Calculate your monthly mortgage payment from home price, down payment, interest rate, term, property tax, PMI, and insurance. The calculator separates principal and interest from estimated monthly add-ons, validates the down payment and term, and shows a P&I amortization schedule so you can see how the balance and payment components change over time.
How this calculator works
Formula
Monthly principal and interest = P × r ÷ (1 − (1+r)^−n); all-in payment adds monthly tax, insurance, PMI estimate, and HOA.
Sources
Sources support the method, terminology, or planning context. Editable assumptions remain your responsibility.
Assumptions to verify
- Fixed rate and level principal-and-interest payments are assumed.
- Property tax and insurance remain constant.
- PMI cancellation rules, closing costs, utilities, and maintenance are not modeled.
Frequently asked questions
How is a monthly mortgage payment calculated?
Monthly P&I equals loan principal multiplied by the monthly rate, divided by 1 minus one plus the monthly rate raised to the negative number of payments.
What does the all-in monthly mortgage payment include?
It combines monthly principal and interest with the entered property tax, PMI estimate, and homeowners insurance amounts.
What does a P&I amortization schedule show?
It shows each scheduled principal-and-interest payment split between interest and principal, along with the remaining loan balance over time.
Cite this tool
BoringToolsKit. “Mortgage Payment Calculator.” boringtoolskit.com/mortgage-payment-calculator/ (reviewed July 2026). Free to reference in articles, syllabi, and answer posts with a link.
Privacy: Inputs and results stay in this browser. Results are planning estimates based on your inputs; verify assumptions and current rules before making decisions.