What this calculator does
Every input on this mortgage calculator maps to a real decision, so the output is something you can act on immediately, not a rough ballpark you'll have to double-check elsewhere.
The mortgage calculator estimates your monthly principal-and-interest payment for a home loan based on the price, down payment, interest rate, and term. It also shows the total interest you'll pay over the life of the loan and a year-by-year amortization breakdown.
How to use the Mortgage Calculator
- Start by entering **Home Price** — this anchors every downstream number in the mortgage calculator.
- Fill in **Down Payment**, **Interest Rate** to reflect your specific situation.
- Set **Loan Term**; the result and chart recalculate the moment you finish typing.
- Review the breakdown card for the components that make up the headline number.
- Use Copy, Share, or Print to save the exact scenario — or star it to keep it in your favorites.
The formula
M = P × r(1+r)^n / ((1+r)^n − 1), where P is the loan amount, r is the monthly interest rate, and n is the number of months.
Worked example
For a $400,000 home with $80,000 down at 6.5% for 30 years, the loan is $320,000 and the monthly payment is about $2,022. Over 30 years you pay roughly $408,000 in interest.
Common mistakes
- Forgetting to include property taxes, insurance, HOA and PMI — the total housing cost is higher than P&I.
- Using APR and interest rate interchangeably — APR includes fees.
- Not stress-testing with a rate 1–2 percentage points higher.
When to use it
Use before making an offer, comparing loan quotes, refinancing, or deciding how much house you can afford.
Pro tips for the Mortgage Calculator
- Save your favorite scenarios by clicking the star icon — they're stored locally, no account needed.
- For big decisions, run best-case, expected, and worst-case scenarios and compare the breakdowns side by side.
- Copy the result to paste it directly into email, Notion, or a spreadsheet cell.
Frequently asked questions
›Does this include taxes and insurance?
No, this shows principal and interest only. Add roughly 1–2% of home value annually for taxes and insurance.
›What is a good mortgage rate?
Rates vary daily. Compare at least 3 lenders and look at APR, not just the headline rate.
›Should I choose 15 or 30 years?
15-year loans have higher payments but far less total interest. 30-year loans offer flexibility with lower payments.
›How much down payment do I need?
Conventional loans typically need 5–20% down. Less than 20% usually triggers PMI.
›Can I pay off my mortgage early?
Most mortgages allow prepayment. Extra principal payments dramatically reduce total interest.
›Is the Mortgage Calculator free to use?
Yes. Every calculator on CalcPilot, including the Mortgage Calculator, is free with no sign-up, no watermark, and no export limit.
›Can I embed the Mortgage Calculator on my site?
Embedding isn't public yet, but you can link directly to this page — the URL is stable and shareable.
Embed this calculator
Drop the Mortgage Calculator into your own site or blog post. Free to use — a small “Powered by CalcPilot” link is appreciated.
<iframe src="https://calcpilot.tools/calculators/mortgage-calculator?embed=1" width="100%" height="720" style="border:1px solid #e5e7eb;border-radius:12px;max-width:720px;" loading="lazy" title="Mortgage Calculator — CalcPilot"></iframe>Related calculators
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