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Loans and Debt

Loan Repayment Capacity Calculator

Estimate the maximum loan repayment you could comfortably afford based on your income and existing expenses, using a simple surplus-based approach.

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Your results

Estimated affordable monthly repayment$1,520.00
Monthly surplus before buffer$1,900.00
Buffer held back$380.00

This is a simple guide only; lenders apply their own, more conservative serviceability assessments.

Calculation breakdown

Surplus
net income − expenses − existing debt repayments
Capacity
surplus × (1 − buffer %)

Worked example

With $5,500 net monthly income, $3,200 of expenses and $400 of existing debt repayments, a 20% buffer suggests around $1,520 a month could realistically go toward a new loan repayment.

Assumptions

  • Not a substitute for a lender's formal serviceability assessment, which includes rate buffers and stricter expense benchmarks.
  • Assumes income and expenses are stable from month to month.
  • Does not account for one-off or seasonal expenses.

How this calculator works

This calculator takes your net income and regular expenses to estimate the monthly surplus available for loan repayments, then applies a buffer you set to leave room for rate rises or unexpected costs. It is a simple affordability check, not a lender's formal serviceability assessment.

Frequently asked questions

Is this the same as what a bank will lend me?

No, lenders use their own detailed serviceability calculators that include a mandatory interest rate buffer, all existing debts and more conservative expense assumptions, so treat this as a starting estimate only.

Why include a buffer in the calculation?

A buffer protects against interest rate rises and unexpected expenses, so you are not stretched to the absolute limit of your income each month.

Should I include all my expenses or just fixed ones?

Include realistic total monthly living expenses, not just fixed bills, since lenders and prudent budgeting both account for variable costs like groceries and transport.

Results are estimates only and are not financial, tax, legal or credit advice.

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