Mortgage Calculators and Home Loan Tools

Where to start

Buying a home comes down to four numbers: how much you can borrow, what the repayments will be, what it costs to get in the door, and how much help you can claim. Each of the calculators below answers one of those questions in about a minute, with no sign-up and no obligation. Used together, they turn a vague sense of “can we afford this?” into a clear picture you can actually plan around.

A calculator is a starting point, not a promise. It gives you a fast, honest estimate based on the figures you enter, which is exactly what you need early on when you are working out a budget and a shortlist. When you are ready to move from estimate to certainty, a broker can turn these numbers into a real pre-approval with a specific lender. Start with whichever question is keeping you up at night, then work through the rest.

Borrowing Power Calculator

The Borrowing Power Calculator is the one most people should run first, because it sets the ceiling for everything else. It estimates the maximum a lender is likely to approve based on your income, your existing debts and commitments, your living expenses, and the number of people who depend on you. Change any one of those and you can watch your capacity move, which makes it a powerful tool for seeing how paying off a car loan or closing an unused credit card can lift what you are able to borrow.

The number it produces already accounts for the serviceability buffer, the roughly three per cent that lenders add on top of the actual rate when they assess you. That is why the figure can look lower than you expect, and why it is far more realistic than simply multiplying your income by a rule of thumb. Treat it as your working budget, then use the repayment calculator to check the monthly cost sits comfortably within it.

Home Loan Repayment Calculator

The Home Loan Repayment Calculator tells you what a given loan will cost you each month. Enter the loan amount, an interest rate, and the term, and it works out the repayment and how it splits between interest and principal. It is the fastest way to sanity-check whether a property is genuinely affordable, because the sticker price of a home matters far less than whether you can live comfortably with the repayment on it.

It is also a planning tool. Nudge the interest rate up by a per cent or two and you can see exactly how a rate rise would hit your budget, which is a much better way to stress-test a purchase than hoping rates stay put. Do that before you buy, keep a buffer for the higher number, and a future rate rise becomes an inconvenience rather than a crisis.

Deposit and LMI Calculator

The Deposit and LMI Calculator answers two linked questions: how much deposit you need, and what it will cost you if that deposit is under twenty per cent. Lenders Mortgage Insurance is a one-off premium that protects the lender, not you, and it applies when you borrow more than eighty per cent of a property’s value. It can run into many thousands of dollars, so knowing the number in advance changes how you plan your savings.

The calculator also shows where the thresholds sit, which matters because the cost of the insurance steps up as your deposit shrinks. Seeing that clearly often changes a buyer’s plan, whether that is saving a little longer to cross a threshold, or using a guarantor or a government scheme to avoid the premium altogether. If the number surprises you, that is exactly the kind of thing worth a conversation before you commit.

Stamp Duty Calculator

The Stamp Duty Calculator covers all states and territories, because stamp duty is a state tax and the rules, rates, and concessions differ everywhere. It is usually the single largest upfront cost after your deposit, and first home buyers are often eligible for a full or partial exemption that can be worth tens of thousands of dollars. The calculator shows both the standard duty and any concession you may qualify for, so there are no nasty surprises at settlement.

Because the concessions have price thresholds that change from state to state, this is a number worth checking early. A property that sits just over a concession cap can cost far more in duty than one just under it, and knowing where those lines fall in your state can genuinely shape your shortlist.

First Home Grants Calculator

The First Home Grants Calculator pulls together the help available to first home buyers, from the First Home Owner Grant to the deposit schemes and shared-equity options, and shows what you may be able to claim based on your state and situation. The support on offer has grown a lot in recent years, and many buyers leave money on the table simply because they do not realise they qualify.

Running it early is worth it because some schemes have eligibility rules, caps, or timing conditions that are easier to meet if you know about them in advance. Combined with the deposit and stamp duty calculators, it gives you a complete picture of what you need to get in the door, and how much of that the government might cover.

Why a bank’s number differs from a calculator

A calculator gives you a realistic estimate, but a lender’s actual assessment can land higher or lower, and it helps to understand why. Every lender has its own policy for how it treats different types of income, such as overtime, bonuses, commissions, self-employed earnings, and government payments. Some count the full amount, some count a portion, and some will not count it at all. Two lenders looking at the same borrower can therefore arrive at very different numbers.

Lenders also assess your existing commitments differently, from how they treat credit card limits to how they weigh a HECS or HELP debt. This is precisely where a broker adds value: rather than guessing which lender will view your situation most favourably, a broker knows the policies across the panel and can point you to the one likely to lend you the most on the best terms. The calculator gets you a confident estimate; the broker gets you the real approval.

Frequently asked questions

Are these calculators free to use?

Yes. Every calculator is free, needs no sign-up, and comes with no obligation. You can run them as many times as you like while you work out your budget and shortlist.

How accurate are the results?

They are a realistic estimate based on the figures you enter and current lending rules, including the serviceability buffer. Your actual approval depends on a specific lender’s policy and a full assessment of your situation, which is the step a broker helps you complete.

Which calculator should I use first?

Start with the borrowing power calculator, because it sets the ceiling for everything else. Then use the repayment calculator to check the monthly cost, and the deposit, stamp duty, and grants calculators to work out what you need to get in the door.

Do you store the numbers I enter?

The calculators are there to help you plan privately. If you decide you want a real approval, you can choose to speak with a broker and share your details then, on your terms.