Finance calculators

Borrowing Power Calculator

Updated Sep 3, 2026 By Jehan Wadia
Rate Formulas

About you

Tell us about your situation — we'll use this to tailor your estimate.

Who is applying?
What are you buying?
Range 0–10.
Assessed separately from children.

Your income

Enter gross (before-tax) amounts. Every figure is converted to an annual amount before it is assessed.

Interest rate used in this estimate
Owner-occupier 6.24% p.a.
Investment 6.54% p.a.
Serviceability is assessed at the applicable rate plus a 3.00% buffer. You can override the rate in the results below.

Your expenses & commitments

Enter what you spend and what you owe. Amounts are converted to a monthly figure for the results and an annual figure for the capacity calculation.

Leave blank (or 0) and we'll estimate your living expenses from your household size and income using a HEM-style benchmark.
Enter the total credit limit across all your cards, not your current balance. Lenders assess credit card risk on the limit available to you (3.8% of the limit per month).

Your estimated borrowing power
$0
Show repayments
Estimated repayment
$0
Repayments as a share of take-home pay
0%
Money remaining each month
$0
After living expenses, commitments and the new loan repayment.
Monthly after-tax income
$0
Where your monthly income goes
Monthly after-tax income breakdown
CategoryMonthly amountShare of income

Borrowing power if rates move
Estimated borrowing power at different interest rates
Interest rateEstimated borrowing power
What if? Explore scenarios
Borrowing power in this scenario
$0
No change from your estimate

These sliders change only this panel — your main estimate above stays as entered.

Step-by-Step Solution

Introduction

The Borrowing Power Calculator shows you how much a lender may let you borrow for a home loan. Enter your income, your bills, and your debts, and it estimates the loan size you could support.

It works for one person or a couple. You can pick a first home, a home to live in, or an investment property. If you buy an investment, the tool adds your expected rent and your tax savings from negative gearing.

The maths follows what real lenders do. It works out your tax and Medicare levy, counts extra income and rent at 80%, and tests your loan at your rate plus a 3% buffer. If you skip your living costs, it fills in a HEM-style estimate for you.

Your results show your loan size, the price of home you could buy with a 20% deposit, your repayment, and how much money you would have left each month. Charts show where your pay goes and what happens if rates rise or fall. The "What if?" sliders let you test more income, lower bills, or a new rate. A step-by-step section shows every number behind the answer.

This is an estimate only. Your real limit depends on the lender, your credit file, and your deposit.

How to use our Borrowing Power Calculator

Enter your income, your expenses and your debts, and this home loan borrowing power calculator shows how much you may be able to borrow, your likely repayment, and how much money you would have left each month.

Who is applying: Pick "Just me" if you are buying alone, or "Two of us" if you are buying with a partner. Picking two adds fields for their income.

What are you buying: Choose your first home, a home to live in, or an investment property. Investment loans use a higher rate and add a rent field.

Dependent children: Use the plus and minus buttons to count kids under 18 who rely on you. More kids means higher assumed living costs.

Dependent adults: Count adults aged 18 and over who you support. These are counted apart from children.

When do you plan to buy: Pick your buying timeframe. This changes the tip you get with your result.

Your income before tax: Type your gross pay, before tax is taken out. Then pick weekly, fortnightly, monthly or yearly to match how you get paid.

Your other income: Add steady extra money like bonuses, overtime, a second job or dividends. Lenders only count 80% of it.

Your partner's income before tax: If you chose "Two of us", type their gross pay and pick the right frequency.

Your partner's other income: Add their regular extra income, such as bonuses or overtime. It is also counted at 80%.

Current rental income: Enter rent you already get from an investment property you own. Leave it at 0 if you have none.

Expected rental income: For an investment purchase, enter the rent you think the new property will earn. This is used for negative gearing too.

Living expenses: Enter what you spend on food, bills, transport, insurance and fun. Leave it at 0 and we will estimate it for you.

Rent you'll pay after buying: If you will still rent your own home after you buy, put that rent here.

Existing home loan repayments: Enter repayments on a mortgage you already have. Do not add the new loan you are working out.

Other loan repayments: Add car loans, personal loans, HECS/HELP and any other set repayments.

Total credit card limit: Enter the total limit on all your cards, not the balance. Lenders count 3.8% of the limit each month.

Other regular commitments: Add things like child support, buy now pay later or school fees.

Custom interest rate: Turn this on in the results to test your own rate. Leave it off to use our default rate.

Loan term: Choose 10 to 30 years. A longer term lifts borrowing power but costs more interest.

Show repayments: Pick weekly, fortnightly or monthly to see your repayment your way.

What if sliders: Move the sliders to test more income, lower expenses or a rate change. Only this panel changes.

Calculate and Reset: Press Calculate to see your results, or Reset to go back to the starting numbers.

What Is Borrowing Power?

Borrowing power is the amount of money a lender thinks you can safely pay back on a home loan. It is also called borrowing capacity. Lenders work it out by looking at what you earn, what you spend, and what you already owe. Whatever money is left over each month is what you can use to make loan repayments.

What Affects How Much You Can Borrow

  • Your income: Your salary before tax is the biggest factor. Bonuses, overtime, side jobs and rent you collect also count, but lenders usually only count about 80% of them because they can stop or change.
  • Living costs: Food, power bills, transport, insurance and fun money. If you enter a low number, lenders will still use a benchmark figure (called HEM) that matches your household size and income.
  • Debts and repayments: Car loans, personal loans, HECS/HELP and rent you keep paying all cut your borrowing power.
  • Credit card limits: Lenders look at your limit, not your balance. A $10,000 limit is treated like a real debt, even if you owe nothing. Around 3.8% of the limit is counted as a monthly cost.
  • People who depend on you: Each child or adult you support raises your costs and lowers what you can borrow.
  • Interest rate and loan term: A higher rate means bigger repayments and a smaller loan. A longer term lowers each repayment but costs more interest overall.

The 3% Interest Rate Buffer

Lenders in Australia must check that you could still pay your loan if rates went up. They add about 3% to the real rate and test you at that higher number. So if the rate is 6.24%, they check your budget at 9.24%. This is why your borrowing power is lower than you might expect.

Owner-Occupier vs Investment Loans

Loans for a home you live in usually have a lower rate than loans for an investment property. If you buy an investment, the rent you expect to earn is added to your income (again, usually at 80%). If the loan interest costs more than the rent, the loss can lower your tax bill. This is called negative gearing, and it can lift how much you are able to borrow.

How to Increase Your Borrowing Power

  • Lower or close credit card limits you do not use.
  • Pay off car loans, personal loans and buy-now-pay-later accounts.
  • Cut regular spending for a few months before you apply.
  • Grow steady income, such as a pay rise or a second stable job.
  • Apply with a partner so two incomes are counted.
  • Save a bigger deposit, which lowers the loan you need and can avoid lenders mortgage insurance.

A Good Rule for Repayments

A common target is to keep home loan repayments under 30% of your take-home pay. Between 30% and 40% is tight, and over 40% leaves little room for surprises like a car repair or a rate rise. Borrowing the maximum you are offered is not always smart. Pick a repayment you can still handle on a bad month.

Note: This is an estimate only. Every lender uses its own rules, and the real amount you can borrow depends on your credit history, job type, deposit size and the property itself. Talk to a mortgage broker or lender before you make an offer.


Formulas used

Maximum loan amount (present value of monthly surplus at buffered rate)
L = P \times \frac{1 - (1 + i)^{-n}}{i}, \quad i = \frac{r + 3.00\%}{12}, \quad n = 12 \times \text{term}
Monthly surplus available to service a new loan
P = \frac{N_{\text{assessed}} + B_{\text{gearing}} - E_{\text{living}} - C_{\text{commitments}}}{12}
Assessable income after shading (other income and rent at 80%)
I_{\text{assessed}} = I_{\text{salary}} + 0.80 \times I_{\text{other}} + 0.80 \times I_{\text{rent}}
After-tax (take-home) income
N = TI - \max(0,\; \text{Tax}(TI) - \text{LITO}(TI)) - \text{Medicare}(TI)
Annual commitments including credit card limit assessment
C = R_{\text{rent paid}} + R_{\text{home loan}} + R_{\text{other loans}} + R_{\text{other}} + 0.038 \times 12 \times \text{CardLimit}
Loan repayment per period at the actual rate
R = L \times \frac{i_p}{1 - (1 + i_p)^{-n_p}}, \quad i_p = \frac{r}{100 \cdot f}, \quad n_p = f \times \text{term}
Negative gearing tax benefit (investment loans)
B_{\text{gearing}} = \max\!\left(0,\; L \times \frac{r}{100} - I_{\text{rent, expected}}\right) \times m
Affordability ratio, monthly surplus and indicative property price
\text{Ratio} = \frac{R_{\text{monthly}}}{N/12} \times 100\%, \qquad \text{Price} = \frac{L}{1 - 0.20}

Frequently asked questions

How much can I borrow on a $100,000 salary?

Most lenders will offer roughly 5 to 6 times your gross income, so about $500,000 to $600,000 on a $100,000 salary.

That figure drops fast if you have debts. A car loan, a big credit card limit, HECS or kids can pull it down by $100,000 or more. A couple both earning $100,000 could borrow close to $1 million if they are debt free.

What income do I need for a $500,000 home loan?

A single person with no other debts usually needs about $100,000 to $120,000 a year.

Here is why. A $500,000 loan at 6.24% over 30 years costs about $3,080 a month. But lenders test you at 9.24% (rate plus the 3% buffer), which is about $4,110 a month. You need enough left over after tax, living costs and debts to cover that higher number.

How many times my salary can I borrow for a home loan?

Around 5 to 6 times your gross yearly income is normal in Australia today.

It used to be 7 or 8 times when rates were near 2%. The 3% stress test and higher rates have cut that back. Lenders do not really use a multiple though. They work from your leftover cash each month. The multiple is just a quick check.

What is a debt-to-income ratio and what counts as too high?

Debt-to-income (DTI) is your total debt divided by your gross yearly income.

Borrow $600,000 on a $100,000 income and your DTI is 6. Banks must report loans with a DTI of 6 or higher as risky, so many will say no or ask for a good reason above that. Under 6 is the safer zone.

What is HEM and why do lenders use it?

HEM stands for Household Expenditure Measure. It is a benchmark of what a household your size and income really spends to live.

If you say you spend $800 a month but HEM says $3,200, the lender uses the higher number. This stops people low-balling their costs to get a bigger loan. HEM grows with your income and with each person you support.

Does HECS or HELP debt lower how much I can borrow?

Yes. Your HECS repayment comes out of your pay, so lenders treat it like any other debt.

On a $100,000 salary you might repay around $7,000 a year. That can cut your borrowing power by $50,000 or more. Paying off a small HECS balance before you apply can help. Paying down a large one usually does not help enough to be worth it.

How much does a car loan reduce borrowing power?

Roughly $120 of loan for every $1 of monthly repayment.

So a $500 a month car loan cuts your borrowing power by about $60,000. A $700 a month novated lease can cost you close to $85,000. Clearing a car loan is often the fastest way to get a bigger home loan.

Does closing a credit card increase how much I can borrow?

Yes, and by more than you might expect. Lenders count about 3.8% of your limit each month, even if you owe nothing.

A $10,000 limit is treated as $380 a month of cost. That alone lowers your borrowing power by roughly $45,000. Cutting the limit works too if you want to keep the card.

Is borrowing power the same as pre-approval?

No. Borrowing power is an estimate based on numbers you type in. Nobody has checked them.

Pre-approval is a real lender decision. They look at your payslips, bank statements and credit file, then agree to lend up to a set amount. Only pre-approval carries weight with a seller or at an auction.

How long does home loan pre-approval last?

Usually 3 months, and some lenders give 6.

You can often renew it if nothing has changed. But rates, lender rules and your own pay can shift, so the amount can go up or down when you renew. Do not sign a contract on old pre-approval without checking it is still valid.

How much deposit do I need to buy a house in Australia?

5% is the usual minimum. 20% is the level where you avoid lenders mortgage insurance.

Also budget about 4% to 5% extra for stamp duty, legal fees and checks. First home buyers may get help through government schemes that allow a 5% deposit with no insurance.

What is LMI and how much does it cost?

Lenders Mortgage Insurance protects the lender if you cannot repay. You pay it when your deposit is under 20%.

It costs about 1% to 5% of the loan. On a $500,000 loan with a 10% deposit, expect roughly $8,000 to $15,000. Most people add it to the loan, which means you pay interest on it too.

Does a bigger deposit increase how much I can borrow?

Not usually. Your loan size comes from your income and expenses, not your savings.

But a bigger deposit does raise the price of home you can buy, since price equals loan plus deposit. It can also drop LMI and win you a lower rate, and a lower rate does lift borrowing power a little.

How much rental income do lenders count for an investment property?

About 80% of the gross rent.

The other 20% covers vacancy, agent fees, rates and repairs. Lenders use a rental appraisal from an agent or valuer, not the figure you hope for. So $600 a week of rent is counted as roughly $480 a week of income.

Do lenders count overtime and bonuses in a home loan?

Yes, but only if it is steady. Most lenders want 6 to 12 months of history, then count about 80% of it.

Shift loadings for jobs like nursing, police and mining are often counted at 100% because they are part of the roster. One-off bonuses and casual overtime are the ones most likely to be ignored.

How long do I need to be in my job before applying for a home loan?

Usually 3 to 6 months in a full time role. Some lenders accept you on probation if you have experience in the same field.

Casual and contract workers often need 6 to 12 months. Self-employed people normally need 1 to 2 years of tax returns, and lenders use your net profit, not your turnover.

Why do lenders offer different borrowing amounts for the same income?

Because each lender sets its own rules. The gap between the highest and lowest offer can be $100,000 or more.

They differ on how they treat overtime, HECS, rental income, credit card limits and living cost benchmarks. Some also use a lower assessment rate. This is why shopping around, or using a broker, can change your result a lot.

Do lenders check my bank statements and spending?

Yes. Most ask for 3 months of statements and read them.

They compare your real spending to the expenses you declared and use the higher figure. Gambling, buy now pay later accounts, missed payments and cash advances all stand out. Tidy up your spending for a few months before you apply.