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Mortgage DTI calculator

Debt-to-Income Ratio Calculator Australia

Estimate total known debt as a multiple of gross annual household income. The result is general information, not a lender assessment or approval.

Last updated 13 July 2026

APRA-aligned definition

Enter income and all known debt limits

DTI equals total known debt divided by gross annual income.

Indicative DTI result

DTI ratio

5.33x

Total known debt

$960,000

Band

Between 4 and 6 times income

Six times this income is $1,080,000. Your entered debt is $120,000 below that mathematical benchmark. This is not borrowing headroom or an approval amount.

What 6 times income means

From 1 February 2026, APRA limits the share of new lending that banks can write at DTI of 6 or more. It is a bank portfolio limit, not an individual eligibility rule. Lenders still assess expenses, repayment buffers, income evidence, credit history, LVR, property and their own policy.

Estimate borrowing power Check repayments

How to calculate debt-to-income ratio

DTI = total known debt limits divided by gross annual income.

APRA's residential mortgage reporting standard includes the proposed housing loan and other known debts. Depending on the lender's information, that can include existing mortgages, personal loans, credit card limits, consumer finance, margin lending, buy now pay later limits and HELP debt.

Worked example

A household earns $180,000 before tax. It proposes a $900,000 mortgage, has $25,000 in credit card limits and a $35,000 HELP balance. Total known debt is $960,000.

$960,000 divided by $180,000 = 5.33 times income.

This does not mean the household can borrow another $120,000. A lender still tests actual repayments at an assessment rate and reviews living expenses, existing commitments and its credit policy.

DTI is not borrowing power

DTI measures debt against gross income. Borrowing power estimates whether assessed income can cover living expenses, existing commitments and stressed repayments. Run the Borrowing Power Calculator separately.

APRA's 6 times income measure

From 1 February 2026, authorised deposit-taking institutions must generally limit lending at DTI of 6 or more to 20% of new owner-occupier lending and separately 20% of new investor lending. APRA describes this as a macroprudential portfolio limit. It is not a ban on an individual loan and it does not guarantee loans below 6 times income.

Some new-dwelling and construction lending, as well as eligible owner-occupier bridging finance, is excluded from the portfolio measure. Lender treatment can still vary.

Common mistakes

  1. Using take-home pay instead of gross annual income.
  2. Entering a credit card balance instead of the approved limit.
  3. Leaving an existing mortgage or study debt out.
  4. Treating the gap to 6 times income as available borrowing capacity.
  5. Assuming a DTI below 6 means a loan will be approved.

Sources

General information disclaimer

This tool provides a mathematical estimate based on the figures entered. It is not financial advice, credit advice, a quote, a lender assessment, borrowing capacity, approval or recommendation. Definitions and lender treatment may vary. Check the result with a licensed credit professional or lender before relying on it.