The total price of the property
Down payment
Calculated value
The yearly interest rate
See how paying extra shortens your home loan
What is a mortgage calculator?
A mortgage calculator is an essential financial tool that helps homebuyers estimate their monthly home loan repayments. By factoring in the property price, your deposit, the loan term, and the interest rate, it provides a realistic breakdown of what you will pay each month and over the lifetime of the loan.
Using this calculator allows you to experiment with different scenarios—such as increasing your deposit or making extra monthly payments—so you can find a comfortable budget before committing to a property.
How to use this calculator
Input the total purchase price of the property you intend to buy.
Adjust the percentage or amount of money you have saved as a down payment.
Enter the expected interest rate and how long you have to pay off the loan.
Add an optional extra monthly payment to see how much interest and time you can save.
What is a deposit?
A deposit (or down payment) is the upfront sum of money you pay toward the purchase price of a home. It is typically expressed as a percentage of the total property price.
A larger deposit means you need to borrow less, which directly reduces your monthly repayments and the total interest you'll pay. Lenders often offer better interest rates to buyers with higher deposits because it represents lower risk.
How interest affects home loans
Interest is the cost charged by a lender for borrowing money. Over a 20 or 30-year term, interest can significantly inflate the total cost of your home.
Even a 0.5% reduction in your interest rate can save you tens of thousands of dollars over the lifespan of a mortgage. Comparing rates from different lenders is one of the most effective ways to lower your long-term housing costs.
Example mortgage calculation
Imagine you are buying a home for $300,000 with a 10% deposit ($30,000).
- You need to borrow $270,000.
- With a 6% interest rate over 20 years.
- Your standard monthly repayment is approximately $1,934.36.
How extra monthly payments can reduce interest
If you decide to pay an extra $200 every month on that same loan, you would pay off your mortgage roughly 3 years and 7 months earlier and save over $44,000 in interest!
Common home loan mistakes
Forgetting to budget for property taxes, insurance, and maintenance.
Stretching your budget to the maximum approved loan limit.
Taking out new debt or opening new credit cards right before applying.
Focusing solely on the interest rate and ignoring loan fees and features.
Not considering the long-term impact of a 30-year vs 20-year term.
Frequently Asked Questions
Related Calculators
Mortgage estimate limitations and references
Payments are modeled monthly using a nominal annual rate divided by 12. Extra-payment term and interest savings are estimates. Property tax, insurance, legal costs, service fees, changing rates and jurisdiction-specific charges are excluded unless shown. Confirm how a lender applies extra payments. Currency selection changes the symbol and suggested rate, not the entered price.
Authoritative references
Important Disclaimer
Calculation method, worked example and reference
What this calculator does and formula: Principal-and-interest payment uses the standard amortization formula P×i(1+i)^N ÷ ((1+i)^N−1). Total housing payment adds entered taxes, insurance and fees.
Variables and units: Enter values in the units named by the controls. The calculator converts through its internal base unit or applies the displayed geometric or financial relationship before rounding the presented result.
Verified worked example: A 100,000 balance at 6% for 30 years produces 599.55 monthly principal and interest.
Result interpretation, assumptions and practical limits: This estimate excludes lender-specific APR treatment, escrow changes, insurance rules and early-payment terms. Verify the Loan Estimate and Closing Disclosure.
Professional check: Treat the result as a planning estimate. Where safety, regulated work, contracts or significant money are involved, verify inputs and the result with the governing standard, manufacturer data and an appropriately qualified professional.