More than just a monthly payment — see exactly where every dollar goes over the life of your loan.
Results update live as you type — no submit button needed. Change the interest rate or term and see the impact on your monthly payment immediately.
Switch between yearly and monthly views to see exactly how much of each payment goes toward principal versus interest at every stage of your loan.
Export a clean one-page mortgage summary PDF — including all key figures and the year-by-year amortisation schedule — to share with a broker or lender.
Choose from 12 currencies including USD, GBP, EUR, AUD, CAD, SGD, and more — all figures display in your selected currency symbol throughout.
A visual breakdown shows what percentage of your total repayment is principal and what is interest — an eye-opening view of the true cost of borrowing.
All calculations run entirely in your browser. Your loan details are never sent to any server — no data collection, no account required.
From first-time buyers to seasoned investors — anyone making a property finance decision benefits from knowing the full numbers.
Understand what you can actually afford before approaching a lender. Compare different loan amounts, terms, and down payment scenarios.
Compare your current loan against a new rate or term. See exactly how much you'd save in interest by refinancing to a lower rate.
Model investment property cashflow by knowing the exact monthly repayment. Compare interest-only versus principal-and-interest scenarios.
Generate a quick PDF summary to share with clients during consultations — shows monthly payment, total cost, and full amortisation schedule.
The standard formula is: M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1], where P is the loan principal, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of payments (years × 12). This produces a fixed payment that covers both interest and principal every month.
Because interest is calculated on the outstanding balance. At the start of the loan, the balance is high — so the interest portion of each payment is large. As the balance decreases over time, more of each payment goes toward reducing the principal. This is called amortisation, and the full schedule shows this shift year by year.
Yes — significantly. A larger down payment reduces the loan principal, which lowers your monthly payment and dramatically reduces the total interest paid over the life of the loan. Try increasing the down payment in the calculator to see the exact savings. A 20% down payment also typically avoids lender's mortgage insurance (LMI/PMI) in most countries.
A 15-year mortgage has higher monthly payments but significantly less total interest paid. A 30-year mortgage is more affordable month-to-month but costs far more in interest over the full term. Use the calculator to compare: enter the same loan amount and rate with 15 vs 30 years and compare the “Total Interest” figure — the difference is often eye-opening.
The amortisation schedule shows the breakdown of each payment into principal and interest, and the remaining loan balance — either by year or by month. In the early years, most of the payment is interest. By the final years, almost all of the payment reduces the principal. Switching to “monthly” view shows every individual payment for the full loan term.
No — this calculator focuses on the principal and interest component of the mortgage payment. Property taxes, homeowner's insurance, and lender's mortgage insurance (LMI/PMI) vary widely by location and lender. Check with your lender for the full PITI (Principal, Interest, Tax, Insurance) figure once you have a specific property and loan offer.
Yes — click the “Download Mortgage Summary PDF” button after entering your details. The PDF includes all key figures (monthly payment, total repayment, total interest) and the full year-by-year amortisation schedule. It is suitable for sharing with a mortgage broker, financial advisor, or lender.
A mortgage is a loan secured against a property. The lender provides the money to purchase the home, and in return you agree to repay the loan — with interest — over a fixed period, typically 15 to 30 years. Understanding exactly what you're agreeing to before signing is one of the most financially important decisions most people make.
Your monthly repayment is calculated using the standard amortisation formula, which ensures the loan is fully repaid by the end of the term with equal monthly payments. Each payment covers the interest accrued that month plus a portion of the principal. In the early months, the majority of your payment is interest because it is calculated on the large outstanding balance. As you pay down the principal, the interest portion shrinks and more of each payment reduces what you owe.
The total interest paid over a 30-year mortgage is often shocking to first-time buyers. A $500,000 loan at 6.5% over 30 years produces monthly payments of approximately $3,160 — and total interest paid of over $637,000. You end up paying more in interest than the original loan amount. This is why shortening the loan term, even by 5 years, or making additional repayments, can save tens of thousands of dollars.
A fixed-rate mortgage locks in your interest rate for a set period — giving certainty over your monthly repayment. A variable rate mortgage can move up or down with market conditions, which means lower payments when rates fall but higher payments when they rise. Many borrowers choose a fixed rate for the initial period (2–5 years) for budget certainty, then reassess. This calculator models a fixed rate — the most common scenario for planning purposes.
The most effective strategies to reduce total interest paid are: increase your down payment to reduce the principal; choose a shorter loan term (15 or 20 years instead of 30); make fortnightly repayments instead of monthly (which results in one extra payment per year); or make occasional lump-sum overpayments when you have surplus cash. Even small additional repayments early in the loan term can shave years off your mortgage and save significant interest.