Mortgage Repayment Calculator Australia
Work out estimated weekly, fortnightly or monthly home-loan repayments for principal-and-interest or interest-only loans, and see your loan-to-value ratio. When LVR is above 80%, lenders mortgage insurance often applies — this page explains that threshold and points to the official First Home Guarantee information. It does not invent LMI premium tables.
How repayments are calculated
Principal-and-interest amounts use the standard reducing-balance formula: the periodic interest rate is the annual rate divided by the number of payments in a year, and the repayment holds the loan to zero at the end of the term. Interest-only amounts are the periodic interest on the full balance. A zero interest rate on principal-and-interest splits the loan evenly across the term.
Interest-only loans in the market are typically limited to a set number of years and then convert to principal-and-interest. This page treats the selected type as applying for the whole term so you can compare the two structures clearly.
Loan-to-value ratio and lenders mortgage insurance
ASIC MoneySmart states that if your LVR is above 80% you may need to pay lenders mortgage insurance, and that LMI is usually payable when the amount borrowed exceeds 80% of the property value. LMI is a cost to the borrower that protects the credit provider, not the borrower.
Insurers set their own premiums. Those tables are not published by ASIC, APRA or any other official source we can cite, so this calculator does not estimate an LMI dollar amount. If your LVR is over 80%, treat LMI as an extra cost to confirm with any lender or insurer you deal with.
First Home Guarantee (Housing Australia)
Eligible home buyers may be able to purchase with a smaller deposit without paying LMI through the Australian Government scheme administered by Housing Australia. The scheme is commonly called the First Home Guarantee and is now also described as the Australian Government 5% Deposit Scheme (it was previously part of the Home Guarantee Scheme).
Housing Australia explains that the guarantee is given to a participating lender and is not a cash grant. Eligibility, property-price settings and ongoing owner-occupier conditions are set by the official scheme rules and can change. Read the current information before you rely on it:
Frequently Asked Questions
How is the loan-to-value ratio (LVR) calculated?
LVR is the loan amount divided by the property value, shown as a percentage. ASIC MoneySmart uses the example of borrowing $450,000 toward a $600,000 home, which is an LVR of 75%. A lower LVR generally means you are borrowing a smaller share of the property’s value.
When does lenders mortgage insurance (LMI) usually apply?
According to ASIC MoneySmart, LMI is usually a one-off cost payable when the amount borrowed exceeds 80% of the value of the property. It protects the lender, not you. This calculator flags that typical threshold. It does not estimate a premium, because LMI prices are set by insurers and are not published as official government tables.
How can some buyers avoid LMI with a smaller deposit?
One official pathway is the Australian Government scheme administered by Housing Australia, known as the First Home Guarantee and now also described as the 5% Deposit Scheme. Eligible buyers may purchase with a smaller deposit without paying LMI, subject to scheme and lender rules. Check current eligibility on the Housing Australia and First Home Buyers websites. This page does not assess whether you qualify.
What is the difference between principal-and-interest and interest-only?
Principal-and-interest repayments reduce the loan balance over the term. Interest-only repayments cover interest for the selected term and leave the principal unchanged in this simple model. Interest-only home loans are usually available only for a limited period and then revert to principal-and-interest. ASIC MoneySmart has a dedicated explainer on interest-only home loans.
Do weekly or fortnightly repayments match what a lender will charge?
This tool divides the annual interest rate by 52 (weekly), 26 (fortnightly) or 12 (monthly). Some loan contracts calculate a monthly repayment and then split it. Your actual schedule can differ. Use the result as a planning figure and confirm the contractual repayment with any lender you deal with.