Calculator
Borrowing Capacity Calculator
Estimate how much you may be able to borrow before lender policy, credit scoring and security position are assessed.
A 92% net surplus ratio is applied to your available monthly surplus as a conservative serviceability buffer. Actual lender assessments vary.
Want these numbers checked? Send the result across and we'll tell you what a lender would make of it. No meeting required.
Borrowing capacity is policy driven
This calculator is deliberately conservative and simple. Real borrowing capacity changes by lender because each bank treats income, overtime, bonus, rent, self-employed income, credit cards, dependants and living expenses differently.
If you are self-employed, investing, buying with a guarantor, or have complex income, a manual assessment will be far more useful than an online estimate. Existing debts drag harder than most people expect: here is how a car loan affects your home loan borrowing power.
Frequently asked questions
How much can I borrow for a home loan?
Borrowing capacity is set by your surplus income, not your total income. A lender takes your gross income, discounts the portion it treats as usable, subtracts your living expenses, existing debt repayments and a loading for credit card limits, then tests what is left against a repayment at an assessment rate well above the actual rate. This calculator runs that same sequence so you can see the shape of the answer before you apply. The figure it returns is an estimate, because every lender weighs those inputs differently.
Why is the assessment rate higher than the actual interest rate?
Lenders test your loan at a buffered rate rather than the rate you would pay, so the loan still works if rates rise. That buffer is the single biggest reason people borrow less than they expect. This calculator defaults to an assessment rate of 9.20% and lets you change it, so you can see how sensitive your capacity is to that one input. Move it a point in either direction and watch the borrowing figure swing.
Do credit card limits reduce how much I can borrow?
Yes, and it is the limit that counts rather than the balance. A card with a $10,000 limit and nothing owing on it is still assessed as though you might draw the full limit tomorrow. This calculator applies a monthly loading of 3.8% of your total card limits, which is a common lender treatment. Closing or reducing unused cards before you apply is one of the fastest ways to lift capacity, and it costs nothing.
Why do lenders give different borrowing capacity on the same income?
Because the policies behind the numbers differ. Overtime, bonus, commission, rental income, self-employed income, dependants, study debt and how living expenses are floored against a benchmark are all treated differently from one lender to the next. The spread between the most and least generous lender on the same file can be substantial. That is the practical argument for a broker: the assessment that matters is the one at the lender whose policy fits your income shape.