Borrowing Power Calculator
A realistic estimate using APRA's 3% serviceability buffer.
Last updated: January 2025 · Built for the 2024–25 financial year
Inputs
Results
Estimated borrowing capacity
$644,239
Monthly surplus
$5,300
Repayment at that loan
$3,967
Assessed at rate + 3% APRA buffer over 30 years.
Results are estimates only. For financial advice, consult a licensed adviser.
Overview
How much can you actually borrow?
Australian lenders use serviceability tests to decide your borrowing capacity. They stress-test your income against repayments at the assessment rate (the actual rate plus a 3% APRA buffer), then subtract a mandated Household Expenditure Measure (HEM) and your existing debts.
This calculator gives a directional estimate by applying the same logic. Each lender tweaks income shading, HEM bands and debt buffers, so final approvals can vary 10-20% from any indicative figure.
Formula
Capacity estimation
Net surplus = Net income − HEM − existing debt repayments Max repayment = Net surplus × shading factor (≈ 0.95) Capacity = PV of Max repayment over 30 yrs at (rate + 3%)
What lenders actually look at
| Lever | Effect |
|---|---|
| APRA buffer | +3% on the actual rate for assessment. |
| HEM | Postcode + family-size minimum living-cost benchmark. |
| Credit card limits | Treated as fully drawn at 3% monthly repayment. |
| HECS-HELP | Reduces income by 1-10% based on slab. |
| LMI | Adds capacity but is paid by you above 80% LVR. |
Pro tips
- •Cancel unused credit cards before applying — instant capacity boost.
- •Three months of clean statements is what most lenders sample.
- •Get conditional approval before bidding at auction.