What interest rate should I use?

Use the annual percentage rate (APR) your lender quotes. This calculator assumes a fixed rate for the whole term.

Is my data sent anywhere?

No. All calculations run locally in your browser and nothing you enter is stored or transmitted.

PITI stands for Principal, Interest, Taxes, and Insurance — the four main components of a typical monthly mortgage payment.

Mortgage Calculator

Estimate your monthly mortgage payment, total interest, and full payment breakdown based on your loan details.

Reviewed October 7, 2026 Runs in your browser — inputs are never stored

Enter your loan details and select Calculate to see your estimated payment.

This tool provides general financial estimates for educational purposes only and is not personalized financial, tax, or investment advice. Consult a licensed financial professional before making major financial decisions.

About the Mortgage Calculator

A mortgage calculator is a financial planning tool that helps homebuyers and property owners estimate their monthly mortgage payment based on loan amount, interest rate, and term. When purchasing a home, understanding your monthly obligation is crucial for budgeting and long-term planning. This calculator uses the standard amortisation formula to split your payment into principal and interest, and adds property tax, home insurance, and HOA fees so you see your true monthly housing cost. Whether you are a first-time buyer comparing loan offers, refinancing an existing mortgage, or planning a future purchase, it provides clear, accurate estimates. It helps you understand how different rates and terms affect total cost, enabling informed decisions about one of the largest financial commitments of your life. By exploring scenarios — a larger down payment, a shorter term — you can find the loan that best fits your budget and goals. Figures are estimates; confirm all details with a licensed mortgage professional before committing.

How to use it

1Enter the home price and your down payment (or loan amount).
2Add the quoted annual interest rate and loan term (e.g. 30 years).
3Include property tax, insurance, or HOA if you want a full monthly housing cost.
4Review principal & interest versus total payment with escrow items.
5Recalculate with different rates or terms before you commit.

Worked example

a $400,000 home with 20% down ($80,000) leaves a $320,000 loan at 6.5% for 30 years. Principal and interest are roughly $2,023 per month. Adding $300 tax and $120 insurance brings the full housing payment near $2,443. Stress-test at 7% to see how a rate change affects your budget.

How it works

How the calculation works

Your monthly principal and interest is based on the loan amount (home price minus down payment), the interest rate, and the number of monthly payments. Property tax, home insurance, and HOA fees are added on top to show your true monthly housing cost.

Formula used

M = P × [ r(1+r)ⁿ ] / [ (1+r)ⁿ − 1 ]

M — monthly principal & interest payment
P — loan principal (amount borrowed)
r — monthly interest rate (annual rate ÷ 12)
n — total number of monthly payments (years × 12)

Example

On a $320,000 loan at 6.5% over 30 years, the principal & interest payment is about $2,023 per month, with roughly $408,000 paid in interest over the life of the loan.

Tips

A larger down payment lowers your loan amount and monthly payment.
Shorter terms mean higher payments but far less total interest.

Who it is for

First-time buyers comparing loan offers, homeowners refinancing, and anyone planning a future purchase who needs to see the true monthly cost of a mortgage including taxes and insurance.

Why it helps

A mortgage is the largest financial commitment most people make; seeing how rate, term, and down payment change both the monthly payment and total interest turns a vague quote into a concrete budget you can compare.

Tips for better results

Enter the APR your lender quotes, not the headline rate — APR includes fees and reflects the true cost.
Compare a 15-year vs 30-year term side by side: the shorter term raises the payment but can cut total interest by hundreds of thousands.
Include annual property tax and insurance in the fields to see your full PITI, not just principal and interest.
Stress-test with a rate 1–2% higher than your quote to check you can still afford payments if rates rise.

Common mistakes to avoid

Forgetting to subtract the down payment from the home price before estimating the loan principal.
Using the headline interest rate instead of the APR, which hides lender fees.
Leaving out property tax, insurance, and HOA fees, so the “monthly payment” understates your real housing cost.
Ignoring PMI, which applies to down payments under 20% and adds to the monthly cost.

Frequently asked questions

A:Yes. Enter your annual property tax, annual home insurance, and monthly HOA fee to see your full estimated monthly payment.

Reviewed for accuracy · Last updated October 7, 2026

Formulas follow standard amortization, present/future value, and compounding mathematics used throughout the financial industry, and are periodically checked against reference calculations.

CalcWisee Editorial Team

Calculator development and formula review

CalcWisee is an independent site founded by Ayman. Every calculator is built from a published formula or official definition, tested against hand-worked examples before it goes live, and corrected promptly when a reader reports an issue to ayman@calcwisee.com.

Expertise: Financial mathematics, Health and fitness formulas, Applied mathematics, Unit conversion standards

References & sources