How much deposit do I need to buy a house?

At 80% LVR: 20% of purchase price plus stamp duty and legal costs. At 90% LVR: 10% plus stamp duty, legal costs, and LMI. At 95% LVR under the Home Guarantee Scheme: 5% plus stamp duty and legal costs, no LMI.

How much can I buy with my savings?

Enter your total cash into the property deposit calculator. It shows maximum purchase price at 80%, 90%, and 95% LVR with NSW stamp duty included for both first home buyers and investors.

What is stamp duty and why does it reduce my buying power?

Stamp duty is a state government tax on property purchases. In NSW on a $1M property, it is approximately $39,500 for investors. It comes from your savings, reducing cash available for deposit.

Do first home buyers pay stamp duty in NSW?

No stamp duty on properties up to $800,000. Reduced rate on $800,000-$1,000,000. Full rates above $1,000,000.

What is the Home Guarantee Scheme 95% LVR option?

Government scheme allowing eligible first home buyers to purchase with 5% deposit and no LMI. Properties up to $1,500,000 in NSW. No income caps.

Why does the calculator deduct $2,500 automatically?

Covers estimated legal and associated costs including conveyancing, property searches, and registration fees.

Does this calculator work for interstate purchases?

Uses NSW rates. Other states have different stamp duty rates and concessions. Contact Buyvest for interstate calculations.

What is the difference between deposit and borrowing power?

Deposit determines maximum price from a cash perspective. Borrowing power is how much a lender will approve based on income and expenses. Both must align.

Can I include a gifted deposit in my total cash?

Yes, with a signed gift letter. Most lenders still require some genuine savings of your own (typically 5% held for 3 months).

Should I use a mortgage broker when buying my first home?

Yes. Compares rates across 35+ lenders, identifies government schemes, checks LMI waiver eligibility. $0 cost.

Mortgage repayment calculator

Mortgage Repayment Calculator - Buyvest

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Mortgage Repayment Calculator

Loan Amount (AUD)

Interest Rate p.a. (%)

Repayment Frequency

Loan Type

Loan Term — Years

Months

Additional Repayment (AUD)

What makes this calculator different

Six calculators in one: repayments, extra repayments, and interest only

Most mortgage repayment calculators do one thing: calculate your monthly repayment at a given rate. If you want to see weekly repayments, you need a different tool. If you want to compare principal and interest with interest only, that is another calculator. If you want to see how extra repayments reduce your loan term, that is yet another separate tool.

Our mortgage repayment calculator combines everything in a single interface. Choose weekly, fortnightly, or monthly repayments. Switch between principal and interest and interest only (with a selectable IO period from 1 to 5 years). Add extra repayments and instantly see the interest saved and the number of years and months cut from your loan term. All results update live as you change any input. No page reloads, no separate calculators, no guesswork.

On a $500,000 loan at 6% over 30 years, adding $200 per week in extra repayments saves $273,026 in interest and reduces the loan term by 12 years and 7 months. Our calculator shows you this in seconds.

Calculator features

What our mortgage repayment calculator includes

Repayment frequencies

Weekly, fortnightly, and monthly. See how switching from monthly to weekly or fortnightly reduces total interest by making more frequent payments against your loan balance. Weekly and fortnightly options are available for principal and interest loans.

Loan types

Principal and interest (P&I) and interest only (IO). Select interest only for 1 to 5 years and the calculator shows both your IO repayment and the higher P&I repayment that kicks in after the IO period ends.

Extra repayments

Enter any additional amount you plan to repay. The calculator instantly shows total interest saved, total repayments reduced, and the exact loan term reduction in years and months. See the real impact of paying even a small amount extra.

Worked examples

See the numbers: $500,000 loan at 6% over 30 years

Weekly repayments — principal and interest — no extra repayments

Weekly repayment$691

Total repayments over 30 years$1,078,452

Total interest paid$578,452

Weekly repayments — with $200/week extra repayments

Weekly repayment (including extra)$891

Total repayments$805,749

Total interest paid$305,425

Interest saved$273,027

Loan term reduction12 years, 7 months

The difference is striking. An extra $200 per week saves $273,027 in interest and takes 12 years and 7 months off the loan. That is the power of extra repayments, and our calculator makes this comparison instant.

Repayment frequency

How weekly and fortnightly repayments save you money

Interest on an Australian home loan is calculated daily on the outstanding balance. When you make more frequent repayments (weekly or fortnightly instead of monthly), you reduce the balance more often, which means less interest accrues between payments.

Fortnightly repayments also create a hidden advantage: there are 26 fortnights in a year, which is equivalent to 13 monthly payments instead of 12. That extra payment each year goes directly to reducing your principal, shortening your loan term without any extra effort. Our mortgage repayment calculator lets you compare all three frequencies side by side so you can see the exact difference in total interest paid.

Weekly repayments

52 payments per year. Aligns with weekly pay cycles. Reduces the outstanding balance more frequently, resulting in less interest accrued over the life of the loan. Available for principal and interest loans.

Fortnightly repayments

26 payments per year (equivalent to 13 monthly payments). Matches fortnightly pay cycles. The extra annual payment reduces the loan term by approximately 4 years on a standard 30-year loan without changing your budget.

P&I vs interest only

Compare principal and interest with interest only loans

A principal and interest (P&I) loan repays both the amount borrowed and the interest from day one. Your repayments are higher, but your loan balance decreases with every payment. Over 30 years, you own your property outright.

An interest only (IO) loan repays only the interest for a set period (typically 1 to 5 years). Your repayments are lower during the IO period, but your loan balance does not reduce. After the IO period ends, the loan converts to principal and interest, and your repayments increase significantly because you now need to repay the full balance over the remaining term.

Our mortgage repayment calculator shows both scenarios. When you select interest only, it displays your IO repayment (monthly) and the higher P&I repayment that applies after the IO period. This helps you plan for the repayment increase and decide whether IO is appropriate for your situation.

When P&I makes sense

Owner-occupied homes where you want to build equity and own the property outright. The standard structure for most home loans. Lower total interest over the life of the loan. Available with weekly, fortnightly, or monthly repayments.

When IO makes sense

Investment property loans where you want to maximise cash flow during the IO period. Interest payments on investment loans may be tax-deductible. Short-term strategy, not a permanent structure. Monthly repayments only during the IO period.

Extra repayments strategy

How extra repayments reduce your loan term and save interest

Every dollar you pay above your minimum repayment goes directly to reducing your principal balance. Because interest is calculated daily on the outstanding balance, even small extra repayments have a compounding effect over time. The earlier you start making extra repayments, the greater the impact.

Our calculator shows three key metrics when you enter an additional repayment amount: the total interest saved compared to minimum repayments only, the reduced total cost of the loan, and the exact loan term reduction in years and months. These figures update live as you adjust the extra repayment amount, so you can experiment with different scenarios.

Small extras add up

Even $50 per week extra on a $500,000 loan at 6% saves tens of thousands in interest and years off the loan term. Use the calculator to see the exact figure for your situation.

Round up your repayments

If your minimum weekly repayment is $691, round up to $700 or $750. The small difference barely affects your weekly budget but accelerates your loan payoff significantly over time.

Use windfalls strategically

Tax refunds, bonuses, and inheritance can be directed to extra repayments. Even occasional lump sums reduce your principal and lower interest for every remaining payment.

Step by step

How to use the mortgage repayment calculator

Enter your loan amount. The total amount you are borrowing (or your current outstanding balance if you are checking an existing loan). Use our property deposit calculator to work out how much you need to borrow based on your savings.

Enter your interest rate. The annual interest rate (p.a.) on your loan. If you are comparing rates, run the calculator multiple times at different rates to see the repayment difference.

Select your loan type. Choose principal and interest (P&I) for standard owner-occupied loans. Choose interest only (IO) and select the IO period (1 to 5 years) for investment or cash flow management scenarios.

Select your repayment frequency. Weekly, fortnightly, or monthly. For P&I loans, compare all three to see how frequency affects total interest. IO loans use monthly repayments only.

Set your loan term. Enter years and months for precise control. Standard terms are 25 or 30 years, but you can enter any term to see how a shorter loan reduces total interest.

Add extra repayments (optional). Enter any additional amount you plan to repay per period. The calculator instantly shows interest saved, total repayments reduced, and exact loan term reduction in years and months.

Planning tools

Use this calculator alongside our other tools

Equity

Home equity calculator

Already own a property? Use our home equity calculator to see how much usable equity you have at 80%, 90%, and 95% LVR with LMI costs factored in.

Deposit

Property deposit calculator

Planning to buy? Our property deposit calculator shows the maximum property price your savings can afford with stamp duty and first home buyer concessions included.

Broker

Speak to Buyvest

Calculators show estimates. Our mortgage broker team confirms your actual borrowing power, compares rates across 35+ lenders, and finds the best loan structure for your situation. $0 cost.

Common questions

Mortgage repayment calculator FAQs

How much are repayments on a $500,000 home loan?

At 6% interest over 30 years with principal and interest repayments: approximately $691 per week, $1,382 per fortnight, or $2,998 per month. Enter your specific loan amount and rate into the calculator above for an exact figure. Rates vary between lenders, and our mortgage broker team can compare rates across 35+ lenders.

How do extra repayments save me money?

Every extra dollar goes directly to reducing your principal balance. Because interest is calculated daily on the outstanding balance, a lower balance means less interest accrues. Over time, the compounding effect is significant. On a $500,000 loan at 6%, an extra $200 per week saves $273,027 in interest and cuts 12 years and 7 months off the loan term.

Are weekly repayments better than monthly?

Weekly and fortnightly repayments reduce total interest because you pay down the balance more frequently. Fortnightly repayments are particularly effective because 26 fortnights equals 13 monthly payments per year (one extra payment annually). This alone can shorten a 30-year loan by approximately 4 years. Use the calculator to compare all three frequencies for your specific loan.

What is the difference between principal and interest and interest only?

Principal and interest (P&I) repayments reduce both the loan balance and the interest. Your balance decreases with every payment. Interest only (IO) repayments cover only the interest charged. Your loan balance stays the same during the IO period. After the IO period (1 to 5 years), the loan converts to P&I with higher repayments because you must repay the full balance over the remaining term.

How long can I have interest only repayments?

Most lenders offer interest only periods of 1 to 5 years for owner-occupied loans and up to 5 years (sometimes 10) for investment loans. Our calculator lets you select 1 to 5 years and shows both the IO repayment and the post-IO P&I repayment so you can plan for the increase.

How much does the interest rate affect my repayments?

Significantly. On a $500,000 loan over 30 years, the difference between 5.5% and 6.5% is approximately $160 per week in repayments and over $250,000 in total interest over the loan life. Even a 0.25% rate difference adds up to tens of thousands over 30 years. Our mortgage broker team negotiates the best rate across 35+ lenders.

Can I make extra repayments on a fixed rate loan?

Most fixed rate loans allow limited extra repayments (commonly $10,000 to $20,000 per year) without penalty. Exceeding this limit may trigger break costs. Variable rate loans typically allow unlimited extra repayments. If extra repayments are important to your strategy, our mortgage broker team finds lenders with the most flexible extra repayment policies.

Should I choose a shorter loan term?

A shorter loan term (such as 25 years instead of 30) increases your repayments but significantly reduces total interest. Use the calculator to compare: enter your loan at 30 years, then change to 25 years and see the difference in total interest and repayment amount. Some borrowers prefer a 30-year term with extra repayments for flexibility (you can stop extra repayments if needed, but you cannot reduce a shorter contractual term).

What happens when my interest only period ends?

Your loan converts to principal and interest repayments for the remaining term. Because you have not reduced the principal during the IO period, and you now have fewer years to repay it, your repayments increase (often by 30% to 40% or more). Our calculator shows both the IO and post-IO repayment amounts so there are no surprises. You can also refinance at this point to secure a better rate or extend the term.

How accurate is this calculator?

The calculator uses standard industry formulas for Australian home loans. Results are estimates based on the inputs you provide. Actual repayments may vary depending on your lender's specific calculation method, fees, and whether the rate is fixed or variable. For variable rate loans, recalculate when rates change. Always confirm exact figures with your lender or contact Buyvest for a personalised assessment.

Found the right repayment? Now find the right rate.

Speak with the Buyvest team to compare home loan rates across 35+ lenders and find the loan structure that matches your repayment goals. $0 cost.

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