Budget planner calculator
See where your money goes each month and what is left over. A clear surplus is the starting point for understanding how much you could comfortably repay on a home loan. This planner runs entirely in your browser, so nothing you enter is sent anywhere or saved.
Last updated July 2026Money coming in
Money going out
This is an educational estimate, not a loan approval, quote or advice. It ignores tax, fees, lender policy and your full circumstances, and nothing you enter is sent anywhere or stored. Actual borrowing capacity and repayments are set by a lender after assessment. Speak with a licensed Australian credit adviser before making decisions.
How to use this planner
- Pick your pay frequencyChoose weekly, fortnightly or monthly at the top, then enter every amount at that same frequency. The results are normalised to a monthly view so income and expenses compare fairly.
- Enter income after taxUse take home pay, not gross salary, because that is the money you actually manage. Include a partner and any steady extra income such as rent received.
- List your living costs honestlyWork through housing, utilities, groceries, transport, insurance, other repayments and lifestyle. Rounding up is safer than rounding down.
- Read your surplusThe surplus is what is left after expenses. Your savings rate shows the surplus as a share of income. Both update instantly as you type.
From surplus to borrowing power
Borrowing power is a lender's estimate of how much you can repay without financial stress. Your monthly surplus is central to that estimate, but a lender does not simply lend against today's surplus. It stress tests the numbers so the loan still works if rates rise or life changes.
A lender typically adjusts your figures in a few ways:
- A serviceability buffer. Under APRA guidance, lenders assess repayments at an interest rate around 3 percentage points above the actual rate, so approvals hold up if rates climb.
- A benchmark for living costs. Lenders compare your stated expenses against a minimum living expense measure and use the higher figure, so under reporting costs will not inflate your capacity.
- Existing commitments. Card limits, buy now pay later, car and personal loans and dependants all reduce the surplus available for a mortgage.
A rough rule of thumb: a healthy, stable surplus and a modest debt load usually points to stronger borrowing power, while a thin surplus or heavy short term debt points to less. This planner shows the surplus. Only a lender can confirm an actual borrowing figure after a full assessment.
Simple ways to grow your surplus
- Reduce or close unused credit card limits, since the limit counts against you even at a zero balance.
- Clear high interest short term debts before you apply.
- Review subscriptions and insurance for duplication or better value.
- Build a genuine savings pattern, which many lenders view as evidence you can manage repayments.
Frequently asked questions
Does this tell me how much I can borrow?
No. It shows your monthly surplus and savings rate, which are inputs to borrowing power. A lender calculates an actual borrowing figure using your full financial position, its own policy and a serviceability buffer.
Is my information private?
Yes. The calculator runs in your browser only. There is no submit button that sends data, no account and no storage. Refreshing the page clears everything.
Why normalise everything to monthly?
People are paid weekly, fortnightly or monthly, but bills arrive on their own cycles. Converting everything to a monthly figure is the fairest way to compare money in against money out.
Keep going
Once you know your surplus, read first home buyer loans or refinancing to see how the numbers apply, learn how to choose a mortgage broker, or browse the calculators hub and the glossary.