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GetReal — Methodology

How the calculations work

Every number GetReal produces can be traced back to a specific formula, regulatory source, or data set. This page documents all of them. If you think something is wrong or oversimplified, this is where to check — and where to tell us.
On this page
01

Serviceability

v1.1 — updated September 2025 (HECS exclusion from DTI)
The rule: lenders must verify that a borrower can meet monthly repayments at the actual interest rate plus a 3 percentage point buffer. GetReal stress-tests at rate + 3.0%. The maximum loan is the one where monthly repayments at the stress rate exactly consume the available monthly surplus.

Serviceability is the third and most nuanced ceiling. It answers: given your income and all your committed expenses, what's the biggest loan you can actually repay?

The stress-test rate

APRA's Prudential Practice Guide APG 223 (August 2022) requires all authorised deposit-taking institutions to assess mortgage applications at a minimum buffer of 3.0 percentage points above the loan's interest rate. GetReal applies this buffer to its current interest rate assumption. See Interest rate assumptions for the rate used.

Stress-test rate = interest_rate + 0.03 Monthly repayment = loan × stress_rate_monthly × (1 + stress_rate_monthly)^360 ÷ ((1 + stress_rate_monthly)^360 - 1) where stress_rate_monthly = stress_test_rate ÷ 12 and 360 = 30-year loan term in months

Monthly surplus

The available surplus is net income minus all committed monthly expenses. GetReal calculates this as:

Monthly surplus = take_home_pay_monthly − HEM_floor // see HEM section − declared_living_expenses // if higher than HEM − existing_loan_repayments − existing_mortgage_repayments − credit_card_monthly_cost // 3% of total limit − rent // if currently renting − school_fees_monthly − private_health_monthly − hecs_monthly_repayment // estimated from income, see HECS section

Maximum serviceable loan

The maximum loan is solved iteratively (binary search): find the highest loan amount where monthly repayments at the stress rate do not exceed the monthly surplus.

Worked example
Take-home pay: $5,200/month (single borrower) HEM floor (metro): $2,480/month HECS repayment: $520/month (estimated at $90k income) Car loan repayment: $430/month ───────────────────────────────────────── Monthly surplus: $1,770/month Stress-test rate: 9.49% (6.49% + 3.0%) Monthly stress rate: 0.7908% Max loan where repayments = $1,770: ≈ $219,000
Lender variation: Individual lenders may apply higher buffers, stricter HEM interpretations, or additional expense categories. GetReal's estimate should be treated as indicative.
↗ Source: APRA APG 223 — Residential Mortgage Lending (August 2022)
02

Debt-to-income ratio

v1.1 — updated September 2025 (HECS excluded from DTI per APRA)
The rule: total debt across all loans cannot exceed 6 times gross annual income. GetReal uses 6× as its DTI ceiling. This is the dominant cap at most mainstream Australian lenders.

APRA's macro-prudential framework directs lenders to limit high-DTI lending. While APRA does not set an absolute hard cap, mainstream lenders have adopted 6× gross income as their practical ceiling. GetReal applies 6× as its upper bound.

Max total debt = gross_annual_income × 6 Max new mortgage = max_total_debt − existing_mortgage_balances − credit_card_limits // full limit, not balance − car_loan_balances − personal_loan_balances // HECS/HELP excluded since 30 Sep 2025

What counts as debt

Debt type How it's counted
Existing mortgages Outstanding balance at time of application
Credit cards Total approved limit across all cards — not the balance
Car loans / personal loans Outstanding balance
HECS/HELP Excluded from DTI since 30 September 2025
BNPL (Afterpay, etc.) Outstanding balance — included if declared
Credit card limits are counted in full regardless of actual balance. A $20,000 limit with a $0 balance still adds $20,000 to total debt. Reducing or closing cards before applying can materially increase borrowing capacity.
Worked example
Gross income (couple): $180,000/year DTI cap (6×): $1,080,000 total debt Existing car loan: − $22,000 Credit card limit: − $15,000 ───────────────────────────────────── Max new mortgage: $1,043,000
↗ Source: APRA macro-prudential policy framework
03

LVR limits

v1.0 — January 2025
LVR (loan-to-value ratio) is the loan as a percentage of the purchase price. Lenders cap LVR based on property type and whether the buyer will live there. LMI is payable when LVR exceeds 80%.

LVR determines how much of a property's value a lender will fund. The higher the LVR, the more risk the lender takes on — so they charge LMI as protection above 80%, and cap the LVR outright at a maximum.

Property type Owner-occupier max LVR Investor max LVR
House 95% 90%
Townhouse 95% 90%
Apartment 90% 80%

These are practical market maximums at mainstream lenders. Individual lenders may apply stricter limits — particularly for apartments in high-density postcodes, small apartments under 50m², studio apartments, or in regional areas with limited comparable sales.

LMI capitalisation: When LMI is added to the loan balance (capitalised), GetReal ensures the resulting LVR including LMI does not exceed the ceiling. A 95% LVR ceiling means the total loan including capitalised LMI is at most 95% of the purchase price.

First Home Guarantee: Eligible first home buyers can borrow up to 95% LVR without paying LMI, with the federal government guaranteeing the difference. GetReal does not currently model this scheme — if you're eligible, your actual ceiling may be higher.
04

Lenders mortgage insurance (LMI)

v1.0 — January 2025 (rates updated May 2026)
LMI is an insurance premium paid by the borrower that protects the lender if the borrower defaults. It's payable when LVR exceeds 80%. The premium is a percentage of the loan amount that varies by LVR band and loan size.

LMI is not optional at high LVR — it's a lender requirement. It protects the lender, not the borrower. The premium can be paid upfront or capitalised into the loan (added to the balance). GetReal assumes capitalisation, as this is the most common approach.

Additionally, stamp duty is payable on the LMI premium itself in most states. GetReal applies state-based LMI stamp duty rates from the lmi_stamp_duty_rates table.

LMI rates

GetReal uses indicative LMI rates from the Home Loan Experts rate table (May 2026), stored in the lmi_rates Supabase table. Rates are segmented by LVR band (15 bands) and loan amount band (5 bands from under $300k to over $1M).

LVR band Loan <$300k $300k–$500k $500k–$750k $750k–$1M Over $1M
80.01–85% 0.70% 0.70% 0.76% 0.76% 0.76%
85.01–90% 1.43% 1.43% 1.43% 1.43% 1.43%
90.01–95% 2.77% 2.77% 3.09% 3.09% 3.09%

Indicative only. Actual rates depend on lender and insurer. Genworth and QBE are the two main LMI providers in Australia.

LMI premium = loan_amount × lmi_rate_pct LMI stamp duty = lmi_premium × state_lmi_stamp_duty_rate Total LMI cost = lmi_premium + lmi_stamp_duty // When capitalised: Total loan = base_loan + lmi_premium // LMI stamp duty is paid upfront (not capitalised)
↗ Source: Home Loan Experts — indicative LMI rate table (May 2026)
05

Stamp duty

v1.0 — January 2025 (rates verified August 2026)
Stamp duty (transfer duty) is a state and territory tax on property purchases. Every state uses a progressive bracket system. GetReal calculates it from bracket tables sourced directly from each state revenue office, stored in the stamp_duty_brackets Supabase table.

Stamp duty is calculated before deposit can be applied — it comes out of your savings first. This is why it matters so much to the deposit ceiling calculation: a $50,000 stamp duty bill on a $900,000 purchase is $50,000 that doesn't become deposit.

General formula (all states)

Duty = base_amount_for_bracket + (purchase_price − bracket_min) × marginal_rate

State-by-state rates (standard, non-FHB, established)

State $500k $800k $1.0M $1.5M
NSW $17,990 $31,090 $40,090 $68,215
VIC (standard) $21,970 $43,070 $55,000 $82,500
VIC (owner-occ ≤$550k) $5,765 $43,070 $55,000 $82,500
QLD $8,750 $24,525 $34,525 $59,525
WA $17,765 $28,453 $37,453 $63,453
SA $21,330 $38,730 $50,730 $81,730
TAS $18,247 $30,247 $38,247 $63,247
ACT $12,800 $25,200 $34,200 $60,200
NT $23,929 $38,422 $49,007 $82,543

Figures are approximate, rounded, non-FHB, established property. Use the stamp duty calculator for precise figures.

NT — formula-based calculation

NT uses a formula rather than bracket tables for purchases up to $525,000:

// Where V = purchase_price ÷ 1000 Duty = (0.06571441 × V² + 15 × V) ÷ 1000 // Above $525,000: flat rate of 5.45% applies Duty = purchase_price × 0.0545

First home buyer concessions

Every state offers some form of FHB relief. Thresholds and taper rates are stored in the stamp_duty_concessions table and applied automatically when you indicate you're a first home buyer in the calculator.

State FHB exemption threshold Taper top
NSW $800,000 $1,000,000
VIC $600,000 $750,000
QLD $700,000 $800,000
WA $450,000 $600,000
SA No duty concession (grant only)
TAS 50% discount on established homes
ACT Full exemption (income-tested, Home Buyer Concession Scheme)
NT $18,601 rebate (phaseout starts at $650k) $723,000
→ Use the stamp duty calculator
06

HECS/HELP

v1.1 — updated September 2025 (APRA exclusion from DTI)
Since 30 September 2025, HECS/HELP balances are excluded from lenders' debt-to-income calculations. HECS does not count toward the 6× DTI cap. However, HECS still reduces borrowing capacity by reducing net take-home pay through compulsory ATO repayment withholding.

The change means HECS no longer affects your DTI ceiling (Ceiling 2). But it still affects your serviceability ceiling (Ceiling 3), because the ATO automatically withholds HECS repayments from your salary above certain income thresholds — reducing the take-home pay available to service a mortgage.

Compulsory HECS repayment rates (2025–26)

Repayment income threshold Repayment rate
Below $54,435Nil
$54,435 – $62,7381.0%
$62,739 – $66,6022.0%
$66,603 – $70,6192.5%
$70,620 – $74,8563.0%
$74,857 – $79,3473.5%
$79,348 – $84,1074.0%
$84,108 – $89,1544.5%
$89,155 – $94,5035.0%
$94,504 – $100,1745.5%
$100,175 – $106,1856.0%
$106,186 – $112,5566.5%
$112,557 – $119,3097.0%
$119,310 – $126,4677.5%
$126,468 and above8.0%

GetReal estimates monthly HECS withholding from gross income and deducts it from take-home pay in the serviceability calculation. If you enter your actual take-home pay (already net of HECS), GetReal does not double-count — HECS withholding is only applied if you declare a HECS debt and the tool is estimating your net income.

↗ Source: ATO — HELP debt repayment thresholds
07

Living expenses — HEM

v1.0 — March 2026 (HEM figures current)
HEM (Household Expenditure Measure) is a minimum living cost benchmark published quarterly by the Melbourne Institute. APRA requires all lenders to apply at least HEM when assessing serviceability — even if the borrower declares lower expenses. GetReal uses HEM as the floor.

HEM covers basic living costs: food, utilities, transport, clothing, and everyday spending. It excludes rent, school fees, and private health insurance — these are added separately. GetReal segments HEM by household type, number of dependants, and location (metropolitan vs regional).

Household type Dependants Metro / month Regional / month
Single0$2,480$2,150
Single1$3,050$2,700
Single2$3,480$3,100
Single3+$3,950$3,520
Couple0$3,680$3,200
Couple1$4,200$3,700
Couple2$4,680$4,150
Couple3+$5,200$4,650

Indicative figures based on JMD Mortgages HEM estimates (March 2026). Actual lender HEM benchmarks vary and are not publicly published.

Metro vs regional: GetReal determines location type (metropolitan or regional) from the buyer's postcode, using ABS ASGS Edition 3 classifications. Metropolitan = all eight GCCSA capital cities. Regional = everything else.

HEM figures are not publicly published by the Melbourne Institute — lenders license them. GetReal uses indicative estimates. If a lender applies a stricter HEM, your actual serviceability ceiling may be lower than GetReal's estimate.
↗ Source: Melbourne Institute — Household Expenditure Measure
08

Interest rate assumptions

v1.0 — updated periodically from RBA
GetReal uses a single representative variable rate based on the RBA cash rate plus average lender margin. This rate is updated periodically — it is not a real-time feed. The stress-test rate is this rate plus the 3% APRA buffer.

All three serviceability ceilings are sensitive to the interest rate assumption. GetReal uses a market-average variable rate rather than any lender's advertised rate, because the tool is designed to give a realistic estimate across lenders, not to reflect any specific product.

Rate component Current assumption
Representative variable rate 6.49% p.a.
APRA serviceability buffer + 3.00%
Stress-test rate 9.49% p.a.
Loan term assumed 30 years, principal and interest

The calculator allows an interest rate override if you have a specific rate in mind — for example, a pre-approval offer from a lender. When overridden, the stress-test rate is still the entered rate + 3%.

Rate last reviewed: August 2026. RBA cash rate: 3.85% (as of August 2026).
↗ Source: RBA — Cash Rate Target
09

Property realism score

v1.0 — January 2025
The realism score estimates what percentage of properties in a suburb would match all of a buyer's criteria (suburb, type, budget, bedrooms, bathrooms, car spaces) based on actual sales from the last year. A score of 100% means 25 or more matching sales per year.

The score is not a count of available listings. It's a signal of how often properties matching your full combination of criteria appear in this market. A tight score on any single factor — especially budget — dominates the result.

Score calculation

raw_score = budget_pct × bedrooms_pct × bathrooms_pct × car_spaces_pct // Each factor is the fraction of sales meeting that criterion. // Factors are independent — assumed not correlated. estimated_matches = raw_score × annual_sales_count display_score = min(estimated_matches ÷ 25, 1.0) × 100 // 25 matching sales/year = 100%

Budget factor (NSW)

For NSW suburbs, GetReal counts exactly how many of the last 13 months' sold properties fall at or below the budget. This is a direct calculation from individual records — no estimation involved.

Budget factor (VIC)

VIC budget scoring uses estimated curves — see VIC methodology below.

Bedroom and bathroom factors (NSW)

Where agency-sourced enrichment data is available (Ray White, McGrath, LJ Hooker), bedroom and bathroom distributions are calculated from actual sold records. For un-enriched properties, national distribution estimates are used as a fallback. Current NSW enrichment coverage: approximately 12% of records.

Grade labels

Grade Score range What it means
Highly Realistic75–100%Strong supply. Regular opportunities.
Realistic55–74%Good supply. Patience needed.
Competitive35–54%Limited supply. Act quickly or compromise.
Tight15–34%Very limited supply. Consider relaxing one criterion.
Very Difficult5–14%Rare supply. Most criteria are binding.
Unrealistic0–4%This combination almost never appears.
→ More detail in the FAQ
10

VIC suburb methodology

v1.0 — January 2025 (VIC data: Q4 2025 VGV report)
Victoria does not publish individual sale records. GetReal estimates VIC budget scores using NSW price distribution curves matched by property type, price bracket, and market depth. This is an estimation approach — not a direct count of VIC sales. GetReal is transparent about this on every VIC result.

NSW has over 146,000 individual sale records, which makes it possible to measure the actual distribution of sale prices around the median — how many sales fall at 80% of median, 90%, 100%, 110%, and so on. This distribution shape turns out to be consistent across NSW with two meaningful variables: price bracket and market depth.

Price brackets

BracketMedian price range
1Under $500,000
2$500,000 – $800,000
3$800,000 – $1,200,000
4$1,200,000 – $1,800,000
5Over $1,800,000

Market depth

Suburbs with fewer than 30 sales per year (thin markets) cluster more tightly around the median — buyers compete hard for the limited stock. Active markets (30+ sales) have wider price dispersion. GetReal uses two depth tiers: active (≥30 sales/year) and thin (<30 sales/year). Three tiers were tested; high-volume and medium-volume suburbs were statistically indistinguishable.

Annual sales count — important note

The annual sales count for VIC suburbs is the rolling 12-month figure from the Q4 2025 VGV report — meaning calendar year 2025, not the trailing 12 months from today. GetReal says "in 2025 (VGV annual data)" not "in the last 12 months" for this reason.

Curve lookup

// For a VIC suburb with median $750k, 45 sales/year, property type: house: bracket = 2 // $500k–$800k depth_tier = active // 45 ≥ 30 ratio = budget ÷ suburb_median // e.g. $650k budget ÷ $750k median = 0.867 budget_pct = interpolate(price_curves, property_type, bracket, depth_tier, ratio) // Curves store percentiles at 9 ratio thresholds: 0.5×, 0.6×, 0.7×, 0.8×, // 0.9×, 1.0×, 1.1×, 1.2×, 1.3×, 1.4×, 1.5× median
Honest limitation: VIC scores are estimates calibrated to NSW market behaviour. Actual VIC distribution may differ — particularly in suburbs with very different housing stock mix or buyer dynamics. Treat VIC scores as directionally useful, not precise.
↗ Source: Victorian Valuer General — Quarterly Property Sales Statistics
11

Data sources

v1.0 — August 2026
Source Used for Update frequency Licence
NSW Valuer General — Bulk PSI NSW individual sale records (146,000+) Daily Open — CC BY
Victorian Valuer General — Quarterly report VIC suburb medians + sales volumes Quarterly Open
Ray White sold listings (API) NSW bedroom/bathroom enrichment Weekly Scraping — best effort
McGrath sold listings (scrape) NSW bedroom/bathroom enrichment Weekly Scraping — best effort
LJ Hooker sold listings (API) NSW bedroom/bathroom enrichment Weekly Scraping — best effort
State revenue offices (all 8) Stamp duty brackets and concessions On legislative change Public
Melbourne Institute — HEM Living expense benchmarks Quarterly (licensed) Licensed — indicative figures used
Home Loan Experts — LMI rates LMI premium estimation As published Indicative
RBA — Cash Rate Target Interest rate assumption base Periodic manual review Public
ABS ASGS Edition 3 Postcode metro/regional classification Static (2021) CC BY
ATO — HECS repayment schedule Estimated HECS withholding by income Annual (July) Public
→ View live NSW enrichment coverage stats
12

Changelog

Date Change Section
Aug 2026 Methodology page created. All formulas consolidated from deposit-faq.html and faq.html. All
Sep 2025 HECS/HELP excluded from DTI calculation per APRA direction effective 30 September 2025. DTI section updated. DTI, HECS
Aug 2025 LMI rates updated to May 2026 Home Loan Experts table. LMI
Jan 2025 Initial methodology documented. NSW individual records pipeline live. VIC curve estimation methodology established. All