Best Investment Property Calculators in Australia 2026

Buying an investment property in Australia without running the numbers first is like navigating without a map. You might get lucky, but the odds are not in your favour. The right set of calculators can reveal whether a property will generate positive cashflow, how much cash you need upfront, what your rental yield looks like, and how depreciation will affect your after-tax position.

The problem is that most calculators are scattered across different websites, each covering only one piece of the puzzle. You end up with five browser tabs open, manually transferring numbers between them. In this guide, we compare the best investment property calculators available in Australia in 2026, explain the six types every investor needs, and show you where to find them all in one place for free.

The Six Types of Property Investment Calculators

Before comparing platforms, it helps to understand the different calculator types and what each one does.

1. Stamp Duty Calculator

Stamp duty (also called transfer duty) is one of the largest upfront costs when purchasing a property. Every Australian state and territory has different rates, thresholds, and concessions. A good stamp duty calculator lets you select your state, enter the purchase price, and choose your buyer type (investor, owner-occupier, or first home buyer) to get an accurate figure.

Why it matters: Stamp duty on a $700,000 investment property ranges from roughly $13,000 in the ACT to over $27,000 in NSW. That difference alone can shift your return calculations by a full percentage point. For a detailed breakdown by state, see our stamp duty guide.

2. Rental Yield Calculator

Rental yield tells you what percentage of the purchase price you are earning back in rent each year. Gross yield uses rental income only, while net yield subtracts holding costs such as rates, insurance, and management fees. This is the most common metric for comparing investment properties at a glance.

Why it matters: A property priced at $500,000 returning $450/week in rent has a gross yield of 4.7%. A property at $800,000 returning $600/week has a gross yield of just 3.9%. Without calculating yield, you might assume the more expensive property is the better investment because it brings in more dollars per week. For more on yield calculations, read our rental yield guide.

3. Cashflow Calculator

Cashflow is the bottom line. It takes your rental income and subtracts every expense: mortgage repayments, council rates, insurance, property management fees, maintenance, water charges, strata levies, and vacancy allowance. The result tells you whether you are putting money in your pocket each week or reaching into it.

Why it matters: Many properties that look attractive on yield alone become cashflow-negative once you factor in all holding costs. A cashflow calculator forces you to account for every dollar leaving your account. See our guide on positive cashflow property in Australia.

4. Deposit Calculator

The deposit calculator tells you how much cash you actually need to purchase a property. It goes beyond the deposit itself to include stamp duty, conveyancing fees, building and pest inspections, loan application fees, and lenders mortgage insurance (LMI) if your deposit is below 20%.

Why it matters: Many investors focus only on saving a 20% deposit and are surprised by the additional $15,000 to $30,000 in transaction costs. A deposit calculator gives you a realistic savings target. Our deposit guide explains the full breakdown.

5. Depreciation Estimator

Depreciation is a non-cash tax deduction that can dramatically improve your after-tax return. Division 43 covers the building structure (2.5% of construction cost per year for properties built after 1985). Division 40 covers plant and equipment items like carpet, blinds, and appliances. A depreciation estimator gives you a ballpark figure before you commission a full quantity surveyor's report.

Why it matters: A newer property can generate $8,000 to $15,000 in annual depreciation deductions. At a 37% marginal tax rate, that translates to $3,000 to $5,500 back in your pocket each year. It can be the difference between negative and positive cashflow after tax. See our depreciation schedule guide.

6. Mortgage Repayment Calculator

A mortgage repayment calculator shows your principal and interest or interest-only repayments based on the loan amount, interest rate, and loan term. While many bank websites offer these, having one integrated with your other calculators saves time and reduces errors.

Why it matters: Mortgage repayments are the single largest expense for most investment properties. A difference of 0.25% in interest rate on a $500,000 loan changes your annual repayments by over $1,200.

Comparison: Investment Property Calculator Platforms in Australia

We evaluated the most commonly used property calculator platforms in Australia based on calculator coverage, accuracy, cost, and whether they are built specifically for investors.

| Feature | PropBuyAI | Domain | REA | Property Tax Calculator (ptc.gov.au) | Mortgage Choice | Your Mortgage | |---|---|---|---|---|---|---| | Stamp duty | Yes (free) | Yes | Yes | Yes | Yes | Yes | | Rental yield | Yes (free) | No | No | No | No | No | | Cashflow | Yes (free) | No | No | No | No | No | | Deposit / upfront costs | Yes (free) | No | No | No | No | Limited | | Depreciation | Yes (free) | No | No | No | No | No | | Mortgage repayments | Integrated | Yes | Yes | No | Yes | Yes | | All-in-one platform | Yes | No | No | No | No | No | | Built for investors | Yes | No | No | No | No | Partially | | AI-powered analysis | Yes | No | No | No | No | No | | Account required | No | No | No | No | No | No | | Cost | Free | Free | Free | Free | Free | Free |

Key takeaway: Most platforms offer one or two calculators, typically stamp duty and mortgage repayments. PropBuyAI is the only platform that provides all five core investment calculators free in one place, designed specifically for property investors. You can access them all from our calculators hub.

How to Use These Calculators Together

Running calculators in isolation gives you fragments of the picture. The real power comes from using them in sequence to build a complete investment model. Here is the order we recommend.

Step 1: Start with rental yield

Begin by calculating the gross rental yield to determine whether the property is worth investigating further. As a general guide, gross yields above 4% in a capital city or above 5% in a regional area are worth a closer look. Use our rental yield calculator to compare multiple properties quickly.

Step 2: Calculate your upfront costs

Use the deposit calculator to determine exactly how much cash you need. This includes the deposit, stamp duty, conveyancing, and inspections. If you are comparing properties in different states, the stamp duty difference alone may influence your decision.

Step 3: Run the cashflow numbers

Plug all your figures into the cashflow calculator. Include every holding cost: mortgage repayments, rates, insurance, management fees, maintenance, water, and strata if applicable. Budget for 2 to 4 weeks of vacancy per year.

Step 4: Estimate depreciation

Use the depreciation estimator to understand your tax deductions. Newer properties built after 2000 typically offer the strongest deductions. Combine this with your cashflow figure and marginal tax rate to see your after-tax position.

Step 5: Stress test your assumptions

Run the cashflow calculator again with the interest rate set 1% higher than current rates. If the property still works at a higher rate, it is a more resilient investment. Also test with 4 weeks of vacancy instead of 2. Properties that only work under optimistic assumptions carry more risk.

For a detailed worked example using all five calculators on a single property, see our investment property calculator guide.

What a Calculator Cannot Tell You

Calculators are essential, but they have limitations. They work with the numbers you provide, and they cannot assess factors that require local knowledge or qualitative judgement.

Property condition. A calculator does not know whether the property needs a new roof, has termite damage, or has a dated kitchen that will deter premium tenants. Always conduct a building and pest inspection.

Suburb dynamics. Calculators do not factor in whether the suburb is gentrifying, losing employers, or about to benefit from a new transport link. Suburb research requires looking at demographic trends, infrastructure plans, and supply pipelines.

Market timing. A property that looks great on paper at today's rent may underperform if the rental market softens. Use calculators as a starting point, then overlay your own market research.

Comparable sales context. Knowing that a property yields 4.5% is useful, but knowing that similar properties nearby sold for 10% less last month is critical. PropBuyAI's AI analysis includes comparable sales data alongside the calculator outputs.

Calculators vs Buyer's Agents: When to Use Each

A common question is whether free calculators can replace the advice of a buyer's agent. The answer depends on your experience level and how many properties you are evaluating.

Use calculators when:

You are screening multiple properties and need to narrow your shortlist quickly
You understand the local market and are comfortable making your own decisions
You want to verify the numbers an agent or seller has presented to you
You are building a financial model for a specific property

Consider a buyer's agent when:

You are buying in an unfamiliar market or interstate
You need someone to handle the entire search, negotiation, and settlement process
You value professional advice on property selection and due diligence

Buyer's agents typically charge $15,000 to $20,000 per purchase. For investors who prefer a DIY approach, free calculators combined with an AI-powered analysis provide most of the same analytical capability at a fraction of the cost. See our comparison of buyer's agents vs DIY property purchasing.

Tips for Getting the Most Out of Property Calculators

Use actual rental data, not agent estimates. Check current rental listings for comparable properties in the same suburb and use the median figure. Agent rent appraisals tend to be optimistic.

Include all holding costs. The most common mistake is underestimating expenses. Council rates, water charges, insurance, and maintenance add up to $5,000 to $10,000 per year for a typical house.

Run multiple scenarios. Do not just run the numbers once at the asking price. Model at your expected purchase price, then 5% above and 5% below. Test different interest rates and vacancy periods.

Compare across states. Stamp duty varies dramatically between states. A property in Queensland or the ACT may offer significantly lower upfront costs than the same property in NSW or Victoria.

Save your calculations. When you are comparing five or six properties, it is easy to lose track. PropBuyAI saves your calculations alongside each listing so you can review them later.

Frequently Asked Questions

What is the best free investment property calculator in Australia?

PropBuyAI offers the most comprehensive set of free investment property calculators in Australia. It includes stamp duty, rental yield, cashflow, deposit, and depreciation calculators all in one platform, built specifically for property investors. You can access all calculators from the calculators hub.

How do I calculate rental yield on an investment property?

Gross rental yield is calculated by dividing the annual rental income by the purchase price and multiplying by 100. For example, a property earning $500/week ($26,000/year) purchased for $600,000 has a gross yield of 4.3%. Net yield subtracts annual holding costs from the rental income before dividing by the purchase price. Use our rental yield calculator for an instant result.

How much stamp duty do I pay on an investment property?

Stamp duty varies by state and purchase price. As a rough guide, expect to pay 3% to 5.5% of the purchase price on an investment property. For a $600,000 property, that ranges from approximately $12,000 in Queensland to over $22,000 in NSW. Our stamp duty calculator gives you the exact figure for your state and purchase price.

Can I use a calculator instead of getting professional financial advice?

Calculators are excellent tools for screening properties and modelling scenarios, but they are not a substitute for professional financial advice. They work with the numbers you input and cannot account for your complete financial situation, tax position, or risk tolerance. Use calculators to narrow your shortlist and build your understanding, then consult a qualified financial adviser or accountant before making a purchase decision.

How accurate are property depreciation estimators?

Online depreciation estimators provide a reasonable ballpark figure based on the property's age and estimated construction cost. For a precise figure, you need a depreciation schedule prepared by a qualified quantity surveyor, which typically costs $600 to $800. The estimator helps you gauge whether depreciation will be material for a particular property before you spend money on a full report.

What is a good rental yield for an investment property in Australia?

In 2026, a gross rental yield above 4% in a capital city or above 5% in a regional area is generally considered solid. However, yield should not be assessed in isolation. A high-yield property in a declining suburb may underperform a lower-yield property in a growth corridor over the long term. Use yield as one input alongside cashflow, capital growth potential, and risk factors.

Try the Calculators

All five investment property calculators are free to use, with no account required. Start with one property or compare several side by side.

Browse all calculators or jump straight to the one you need:

Want the full picture? PropBuyAI's AI-powered analysis combines all of these calculations with comparable sales, suburb data, risk assessment, and offer strategy into a single report. Your first analysis is free. Create your account and paste in any realestate.com.au listing to get started.