Why use this calculator
Almost nobody knows what they actually spend. Ask a household to estimate its monthly outgoings and the answer typically lands twenty to thirty per cent below what the bank statement shows, because the small recurring charges are invisible and the irregular costs like registration, insurance and school fees are forgotten entirely.
A budget written down and tested against income is the single cheapest financial intervention available: it costs nothing, it takes half an hour, and it usually finds several hundred dollars a month that were leaking without anybody deciding to spend them. This calculator does the arithmetic and then does the harder part, which is showing you the shape of your spending as percentages so you can see whether the problem is housing, lifestyle or simply that nothing is being set aside.
How to use it
- Enter your monthly take-home pay, which is the figure that actually reaches your account after tax, not your advertised salary.
- For rent or mortgage, use your housing payment including strata or body corporate fees.
- Take groceries from an average of the last three months of statements rather than a guess.
- For transport, add fuel, fares, servicing and tolls, then add one twelfth of your annual registration and tyre cost.
- Divide each quarterly utility bill by three so winter power is spread across the year.
- Convert every insurance premium from its renewal notice to a monthly figure.
- Enter dining, subscriptions and entertainment together, keep personal spending separate, then enter whatever you already transfer to savings, and put everything left over in the other row.
What each result means
- Monthly surplus or deficit
- What is left after every category, including the savings you already make. A surplus without a destination almost always gets spent.
- Savings rate
- The share of take-home pay you keep, counting both deliberate savings and any leftover surplus. It is the number that decides how soon you have choices.
- To reach a 20 per cent savings rate
- How much more you would need to save or stop spending each month for savings plus any surplus to reach 20 per cent of take-home pay, the savings share in the 50/30/20 guideline. If you are already there it shows the margin.
- Total monthly outgoings
- Everything you told the calculator you spend or set aside, which should be close to your average monthly card and account activity.
- Needs: housing, food, transport, utilities, insurance
- The spending that is genuinely difficult to cut this month. When this exceeds 50 per cent of pay, the fix is usually structural rather than behavioural.
- Wants: dining, entertainment, personal, other
- Discretionary spending. This is the fastest category to change and the one that quietly expands whenever income rises.
- Savings and investments
- What you deliberately set aside before any surplus is counted. Automating this on pay day is what separates intention from outcome.
- Needs budget at 50 per cent
- The essentials budget the guideline allows at your income, useful as a ceiling when you are deciding what rent or repayment you can carry.
- Wants budget at 30 per cent
- The lifestyle budget the guideline allows. Exceeding it is only a problem if the savings row is also short.
- Savings target at 20 per cent
- The guideline savings figure, excluding employer super. Hitting it consistently is what builds a deposit or an emergency fund.
- Annual surplus or deficit
- Twelve months of the same result. Small monthly numbers become surprisingly large once they are annualised, in both directions.
The formula
Needs = rent + groceries + transport + utilities + insurance, all in dollars per month
Wants = entertainment + personal + other, in dollars per month
Total outgoings = needs + wants + savings
Surplus = take-home pay minus total outgoings
Savings rate = (savings + any positive surplus) divided by take-home pay, times 100, expressed as a percentage
The 50/30/20 guideline budgets are simply take-home pay multiplied by 0.50, 0.30 and 0.20 respectively. Employer superannuation, currently 12 per cent of ordinary time earnings under the super guarantee, is deliberately excluded because it never reaches your bank account.
How this number is used in practice
The 50/30/20 split was popularised as a rule of thumb for American households and it travels to Australia imperfectly, because housing here takes a much larger share of income in the capital cities. A renter in inner Sydney or Melbourne can be financially careful and still show needs above 60 per cent, which the guideline reads as failure.
The useful response is not to pretend the rent is smaller but to accept that the wants row has to carry the difference, and to treat the 20 per cent savings line as the one that must not move. Where needs genuinely cannot fit, the decisions that matter are the big ones: housemates, a suburb further out, a cheaper car, or a pay rise.
The second thing a budget exposes is the annual costs that never appear in a monthly view. Registration, insurance renewals, tyres, dentist visits, school fees, Christmas and one holiday are collectively worth thousands of dollars and they land in lumps. Households that budget only for the twelve regular monthly bills meet these with a credit card and then wonder why the balance never falls.
The fix used by every financial counsellor is a separate account funded monthly with one twelfth of the annual total, sometimes called a sinking fund or a bills account, so the lump is already paid for when it arrives.
Finally, remember what this calculator deliberately leaves out. Employer superannuation at 12 per cent of ordinary time earnings is real saving and it is not in your take-home pay, so your true savings rate is higher than the figure shown here. For someone on an average full-time wage, adding the super guarantee typically lifts the effective savings rate by around nine to ten percentage points of take-home pay.
That is a genuine cushion, but it is locked away until preservation age, so it cannot pay for a deposit, a car repair or a redundancy.
Worked examples
A single earner on $5,000 a month with $1,600 rent, $600 groceries and $500 already going to savings
A $550 monthly surplus and a 21.0 per cent savings rate, with needs at 63 per cent of pay against the 50 per cent guideline
A dual-income household on $9,000 a month with a $2,600 mortgage and $1,800 invested every month
A $1,200 surplus and a 33.3 per cent savings rate, with needs at 53 per cent and wants at 14 per cent
A renter on $4,200 a month whose rent has risen to $1,900 and who saves nothing
A $270 monthly shortfall and a 0.0 per cent savings rate, with needs consuming 85 per cent of take-home pay
When people use it
- Building a first household budget from bank statements rather than guesswork
- Finding out why the money runs out before the next pay lands
- Testing whether a rent increase or a new loan repayment actually fits
- Setting a realistic monthly savings target for a house deposit
- Reviewing spending after a pay rise, a new baby or a move interstate
- Preparing figures before a session with a free financial counsellor
Tips
- Use three months of bank statement averages, not estimates. Almost everyone underestimates their own spending, usually by twenty to thirty per cent.
- Move savings on pay day by automatic transfer. Saving what is left at the end of the month reliably produces nothing left at the end of the month.
- Open a separate bills account and fund it monthly with one twelfth of your annual registration, insurance and renewal costs.
- Check the subscriptions line specifically. Small recurring charges are the most common source of spending nobody remembers authorising.
- If needs exceed 50 per cent of pay, look at the three big levers first: housing, transport and insurance. Trimming coffee will not close a housing gap.
- Re-run the budget whenever income changes. Lifestyle expands to fill a pay rise within about two months unless the savings transfer is increased first.
- Add your employer super contributions when you judge your overall savings rate, but never when you are planning what you can spend this month.
What it assumes, and where it stops being accurate
- Assumes take-home pay is stable month to month. Casual, commission, seasonal and gig income needs the lowest realistic month entered, not the average.
- Excludes employer superannuation from both income and savings, because it never reaches your bank account. Your real savings rate is higher than the figure shown.
- Assumes annual and quarterly costs have been converted to monthly amounts. Entering only the twelve regular monthly bills will overstate your surplus.
- Excludes tax, because the input is take-home pay. Sole traders and contractors must first set aside tax and GST before entering what is left.
- Excludes debt balances and interest. A surplus here says nothing about whether you should direct it at a credit card, the mortgage or an investment.
- The 50/30/20 split is a guideline drawn from general household data, not a regulated standard or personal financial advice.
Terms used on this page
- Take-home pay
- What reaches your bank account after income tax, the Medicare levy and any salary sacrifice, sometimes called net pay.
- Savings rate
- The share of take-home pay you keep rather than spend, expressed as a percentage.
- Sinking fund
- Money set aside monthly for a known future lump sum such as registration, insurance or a holiday.
- Discretionary spending
- Spending you could stop next month without materially changing how you live, the wants row of the budget.
- Super guarantee
- The compulsory employer superannuation contribution, currently 12 per cent of ordinary time earnings.
Questions people ask
- What exactly is the 50/30/20 rule?
- It allocates half of take-home pay to needs such as housing, food, transport, utilities and insurance, thirty per cent to wants like dining, entertainment and hobbies, and twenty per cent to savings and extra debt repayment. It is a rough guideline for checking the shape of a budget, not a regulated standard or a personal recommendation.
- What counts as a good savings rate?
- Ten to fifteen per cent of take-home pay is a solid outcome for most Australian households and twenty per cent is the common target. People pursuing early financial independence often save far more. Any consistent rate beats an inconsistent one, because the habit matters more than the percentage in the first few years.
- Should employer super count towards my savings rate?
- Count it when you are assessing long-term wealth, because the super guarantee of 12 per cent of ordinary time earnings is genuine saving. Do not count it when you are planning monthly cash flow, since you cannot access it until preservation age and it cannot fund a deposit, a car repair or a period out of work.
- My needs are well above 50 per cent. Is my budget broken?
- Not necessarily. In the Australian capital cities housing alone frequently exceeds forty per cent of take-home pay for renters and recent buyers. The guideline was never calibrated for those markets. What matters is whether the savings line still gets funded once the wants row absorbs the difference.
- How do I budget for irregular annual bills?
- Add up every annual and quarterly cost, including registration, insurance renewals, tyres, medical excess, school fees and holidays, then divide by twelve and treat that figure as a monthly bill. Send it to a separate account automatically. The lump is then already funded when the invoice arrives.
- What should I do with the surplus this shows?
- Give it a specific job before the month starts. The usual order is a small starter emergency fund of a few thousand dollars, then any debt charging more than about eight per cent, then a fuller emergency fund of three to six months of needs, then longer-term investing or extra loan repayments.
Use this with
Budget Planner Calculator answers one part of the question. These pick up where it stops: Emergency Fund Calculator, Savings Goal Calculator, Net Worth Calculator and Rent Affordability Calculator.
Where these figures come from
Figures and rules on this page follow Australian law and ATO guidance.
- Moneysmart: Budgeting. ASIC guidance on building and reviewing a household budget
- Australian Bureau of Statistics. Household income, spending and cost of living statistics
- ATO: Super guarantee and contribution caps. SG rate 12% and the maximum contribution base
Budget Planner Calculator produces an estimate for general information. It is not financial, tax, medical, legal or engineering advice. read the full disclaimer. Spotted a wrong number? Report it and it gets fixed. The form picks up this calculator and the inputs you used.