Calculator
Mortgage Affordability Calculator
Estimate a simplified property budget from annual income, an income multiple, saved deposit, and recurring debt payments.
Result
Estimated borrowing capacity
$360,000.00
Estimated property budget before debt adjustment
$440,000.00
Debt adjustment estimate
$24,000.00
Estimated adjusted property budget
$416,000.00
How to use this calculator
What this calculator does
Estimate a simplified property budget from annual income, an income multiple, saved deposit, and recurring debt payments.
How to use it
Enter your gross annual income, income multiple, deposit saved, and estimated monthly debt payments, then review the result, formula, example, and FAQs below. Try a few scenarios to see which inputs move the result most.
What the result means
Use the result as a direct calculation from the values you entered. If it looks off, check the inputs and formula shown on this page.
Browse more property & housing calculators for related estimates and comparisons.
Results are estimates for planning and education. Actual outcomes depend on local property prices, interest rates, taxes, fees, insurance, maintenance, rental demand, lender rules, tenancy terms, and personal circumstances.
Scenario guidance
When to use this
Use this when making an early property budget estimate before lender pre-approval or detailed affordability checks.
Example scenario
A buyer with $90,000 gross annual income and an $80,000 deposit wants to see how a car payment could affect a rough purchase budget.
Inputs that usually matter most
- Gross annual income, because the estimate starts from income.
- Income multiple, which is a rough assumption and not a lender approval rule.
- Deposit saved and debt payments, because they can change the estimated budget.
Common mistake to avoid
Do not treat an income multiple as lender approval; lenders use their own rates, stress tests, credit checks, documentation, debt rules, and property criteria.
How to interpret the result
Use borrowing capacity, debt adjustment, and adjusted budget as rough planning numbers. Confirm affordability with lender rules, interest rates, taxes, insurance, living costs, and personal cash flow.
Results are estimates and are not mortgage, property, tax, legal, or financial advice.
Formula
Borrowing capacity is gross annual income multiplied by the income multiple. Debt adjustment estimates how recurring debt may reduce the simplified property budget.
Worked example: income multiple budget
$90,000 annual income at a 4x multiple gives $360,000 estimated borrowing capacity. Adding an $80,000 deposit gives $440,000 before debt adjustment. $500 in monthly debt payments creates a $24,000 adjustment, leaving a $416,000 estimated adjusted property budget.
Frequently Asked Questions
Does this guarantee mortgage approval?
No. Lenders use their own rules for income, debt, credit, property type, rates, stress tests, and documentation.
Why include monthly debt payments?
Recurring debt can reduce borrowing capacity, so this calculator uses a simple annualized adjustment.
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