calx.io/Borrowing Power Calculator
See how much you could borrow for a home loan, based on your income, expenses and a lender-style interest rate buffer.
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You will need: income, existing debts, deposit, living expenses.
Your Income
Variable income is shaded to 80% by most lenders
Lenders typically shade rental income to 80%
Dividends, business or self-employed income, etc. Shaded to 80%
Loan Details
Used to estimate your LVR, LMI, and maximum purchase price
Assessment rate: 9.50%. Lenders usually test your loan at your rate plus a 3% buffer.
Existing Debts
Lenders assess existing commitments against your income. Leave blank if not applicable.
Assessed at 3.8% of limit per month regardless of balance
Household & Living Expenses
Household Expenditure Measure (HEM) floor for your household: $2,100/month (scales with income). HEM is the benchmark lenders use for minimum living costs; the higher of your declared expenses and HEM is used.
Estimates only, not financial advice. Actual borrowing capacity varies by lender, credit history, and individual circumstances. LMI estimates are indicative and vary by lender, loan size, and LVR. Consult a mortgage broker or lender for a formal assessment.
Frequently asked questions
How is borrowing power calculated?
The same way lenders assess serviceability. Your salary is converted to after-tax income, other income is shaded to 80%, living expenses use the higher of your declared figure and the HEM benchmark, existing debts and HECS/HELP repayments are deducted, and the remaining surplus is converted to a loan using your interest rate plus a 3 percentage point buffer.
What is the APRA 3% buffer?
APRA, the Australian banking regulator, requires lenders to check you could still afford repayments if rates rose 3 percentage points above your actual rate. That buffer is why you cannot borrow as much as the raw repayment maths suggests.
What is HEM and why does it override my expenses?
The Household Expenditure Measure is the benchmark lenders use for minimum living costs, scaled by household type, dependants and income. If you declare less than the benchmark, lenders (and this calculator) use the benchmark instead, because underestimated expenses are the most common reason applications are revised.
What are LVR and LMI?
LVR (loan-to-value ratio) is the loan amount as a percentage of the property value. Above 80% LVR most lenders charge LMI (Lenders Mortgage Insurance), a one-off premium that protects the lender, not you. The calculator estimates both from your deposit.
Why is this estimate lower than other calculators?
Many calculators service the loan against gross income, which overstates capacity. calx.io uses net (after-tax) income, income-based HECS/HELP repayments and an income-scaled HEM floor, which is how lenders actually assess applications. A lower, realistic number is more useful than a flattering one.