Property equity is the difference between what your home is worth and what you owe on it. The Equity Effect calculator applies growth or decline scenarios to your property value and shows how your equity, your LVR and your usable equity change as a result.
Home equity is the current market value of a property minus the outstanding mortgage balance, and it rises when values increase or when the loan is paid down. Two forces move it. Market growth lifts the value. Repayments reduce the loan. Both build equity over time.
The word "effect" matters. Most owners know their equity has grown, but few know how sensitive it is. Because your loan is fixed and your value isn't, a small percentage change in the market produces a much larger percentage change in your equity. That's leverage at work, and it cuts both ways.
The calculator is built for owners who are thinking about renovating, refinancing, buying an investment property, or simply tracking net worth. It's also useful when the market is moving and you want to see what a fall, or a rise, would mean before you act.
Equity equals current property value minus your loan balance. Usable equity equals 80% of the property value minus your loan balance. The 80% cap reflects the LVR limit many lenders apply before charging lenders mortgage insurance, so it's a practical borrowing measure, not a guarantee.
Here's how to use the calculator:
You own a home worth $900,000 with a $500,000 loan. Your equity is $400,000. Your usable equity at 80% is $720,000 minus $500,000, or $220,000.
Now test three scenarios:
| Scenario | New value | Equity | Usable equity (80%) |
|---|---|---|---|
| Market falls 5% | $855,000 | $355,000 | $184,000 |
| No change | $900,000 | $400,000 | $220,000 |
| Market rises 5% | $945,000 | $445,000 | $256,000 |
A 5% rise in a $900,000 property with a $500,000 loan lifts equity by $45,000, which is an 11% increase in equity from a 5% increase in value.
These are hypothetical figures, not forecasts. They show how leverage magnifies market moves in both directions.
Usable equity can serve as the deposit and costs for another purchase without selling your home. A broker can structure it so the borrowing is separate and clearly documented.
Renovations that add value increase your equity. Model the expected value gain against the cost before you commit.
A lower LVR can open sharper rates. If your equity has grown, you may have more lenders and better pricing available.
If values fall, your equity shrinks, and your usable equity can shrink faster. Seeing that in advance helps you avoid over-borrowing at the peak.
You can access equity through a top-up on your existing loan, a separate loan split, a line of credit, or a full refinance. Each has different rates, structures and tax implications, so the right choice depends on what you plan to use the money for.
| Option | How it works | Best for | Watch out for |
|---|---|---|---|
| Loan top-up | Increase your existing loan | Renovations, personal use | Mixes purpose with existing debt |
| Separate loan split | New loan secured on your home, kept separate | Investment purchases | Set-up and structure matter for tax |
| Line of credit | Revolving limit against equity | Flexible, irregular needs | Variable rates, discipline needed |
| Full refinance | New lender, new loan, optional cash-out | When your current rate isn't competitive | Discharge and application costs |
Keeping equity release borrowings in a separate loan split from your home loan makes it easier to track interest and to show what the funds were used for, which matters for tax on investment borrowing.
Tax treatment depends on how the money is used, and it's the area where advice matters most. Speak with a registered tax professional about your situation, and see MoneySmart for independent guides on borrowing against your home.
Most lenders will let you borrow up to 80% of your property's value without charging lenders mortgage insurance (Mozo, 2026), and you can usually borrow more if you accept LMI. Your usable equity is that limit minus your existing loan. Serviceability, meaning your income and expenses, can reduce it further.
LVR is only one gate. Lenders also assess whether your income can support the new repayments. A big equity figure doesn't mean a big borrowing figure if your income, debts and living costs don't stack up. Ask a broker to run a proper serviceability check.
Two more things to keep in mind. Lender valuations often differ from your estimate, and a lower valuation shrinks usable equity immediately. And borrowing against equity increases your repayments and your risk, so it needs a plan.
Use the LVR Calculator alongside this tool to see the ratio at each stage, and read the LMI guidance on that page if you're thinking about going above 80%.
You need enough usable equity to cover the new deposit and buying costs, plus enough income to service both loans. As a rule, the equity you release funds the deposit, and the new property's own loan covers the rest. Lender serviceability rules decide whether the numbers work.
Take the earlier example, with $220,000 of usable equity. Suppose you want to buy a $600,000 investment property. A 20% deposit is $120,000, and stamp duty, legal and loan costs add more. Your usable equity could cover both, leaving a buffer. Your new loan would then be roughly $480,000, plus the $120,000 to $150,000 borrowed against your home, so your total debt rises.
Buying an investment property with usable equity means borrowing against your home for the deposit, so total debt rises even though no cash savings are used.
That's why serviceability matters as much as equity. Lenders test your ability to repay at a higher assessment rate. Rental income from the new property counts only in part. A broker can model the full picture, and the Buying Costs Calculator shows how much cash to set aside for costs.
Renovating changes your equity only if the renovation adds more value than it costs. Cosmetic work often adds value cheaply. Structural or luxury work often doesn't pay for itself. Model the expected value gain in the Equity Effect calculator before you commit any money.
Suppose you spend $60,000 on a kitchen and bathroom update in a $900,000 home. If a valuer lifts the value to $960,000, your equity rises by $60,000 minus what you borrowed, and you've broken even on value while enjoying the upgrade. If the value lifts only $30,000, you've lost $30,000 of equity on paper. Get a local appraisal before you start.
Borrowing for a renovation also raises your LVR. Check it in the LVR Calculator first, so you don't cross 80% by surprise.
The Hub calculator is built by a brokerage that works with investors every day. It gives you a quick yield, then connects to tools that go deeper, including suburb research and portfolio analysis, in one free account. A broker can review your shortlist afterwards.
The Equity Effect calculator is a new addition to the ICM Hub, joining tools that help you research suburbs, profile your portfolio and ask questions of an AI assistant. It's built by a brokerage that can turn your equity numbers into a lending strategy.
Clients who track their equity often use it to expand their portfolio or improve their loan, and the outcome depends on how much they can safely borrow. Here are two examples from the Investors Choice Mortgages client stories.
Sarah K. from Melbourne refinanced and released equity, saving $340 a month with a three-week turnaround. Michael T. from Sydney bought his second investment property, achieving a 7.2% yield.
Outcomes like these depend on each client's income, property and market timing. They aren't a promise that you'll get the same result.
Equity is one of the biggest assets most Australians hold. Use the Equity Effect calculator to see how market movements change it, then talk to a broker about how to use it.
Call 1800 46 48 10 or email askus@investorschoice.com.au. You can also read about equity release or explore our other property calculators.
