Home Loan Repayment Calculator

Use our home loan repayment calculator (also called “mortgage calculator”) to estimate monthly repayments precisely based on loan amount, interest rate, and loan term and repayment frequency.

Easily estimate your future repayments by adjusting the loan amount, interest rate, and loan term directly within the calculator, allowing you to visualize different scenarios and find the repayment plan that best suits your budget.

Understanding Your Results

This mortgage repayment calculator estimates your total loan repayments, total interest charged, and monthly repayments based on your loan amount, loan term, repayment type, interest rate, and repayment frequency.

You can adjust the inputs and see how each scenario will affect your mortgage repayments. For example, if you borrow $550,000 over 30 years at a 5.9% interest rate with Principal & Interest monthly repayments, you’d pay approximately $3,262 per month. By the end of the term, your total repayments would be around $1,174,410, with $624,410 in total interest.

These results highlight how even a moderate interest rate, applied over a long term, can increase the overall cost of your loan. Use this information to explore different loan amounts, terms, and interest rates before making a final decision.

How Is Mortgage Repayment Calculated?

Mortgage repayment is typically calculated using the amortisation formula, which ensures that you make equal payments over the life of your loan. The formula used is:

M = P ×

r(1 + r)ⁿ


(1 + r)ⁿ – 1

Here’s what each symbol represents:

• M is the periodic repayment amount (for example, your monthly payment).
• P is the principal, or the total loan amount.
• r is the periodic interest rate, which is the annual interest rate divided by the number of payments per year (e.g., for monthly payments, divide the annual rate by 12).
• n is the total number of payments over the loan’s term (for instance, for a 30-year loan with monthly payments, n=30×12=360n = 30 \times 12 = 360n=30×12=360).

This formula calculates a fixed payment amount that covers both the interest accrued and a portion of the principal in each period. In the early stages of the loan, a larger share of your payment goes towards interest, while over time, more of your payment is applied to reducing the principal.

What Factors Influence My Monthly Repayment Costs?

There are 5 primary factors that affect your monthly repayment amount. They are:

• Loan Amount: The total amount you borrow directly affects your repayment size.
• Loan Term: The length of time over which you repay the loan, shorter terms generally mean higher monthly payments, while longer terms lower your payments but increase total interest paid.
• Interest Rate: A higher rate increases your monthly cost, whereas a lower rate decreases it.
• Repayment Type: Choosing between Principal & Interest or Interest-Only repayments will impact how much of your monthly payment goes toward reducing the principal versus paying interest.
• Repayment Frequency: Whether you choose to pay monthly, fortnightly, or weekly can slightly alter your repayment schedule and total interest over time.