Methodology and Sources

calx.io is a set of Australian financial calculators built on one principle: trust through accuracy. Every rate comes from published Australian Taxation Office (ATO) or state revenue office material, every calculation runs in your browser, and every calculator links to its sources. There are no ads, no accounts and no tracking of your figures.

You will see calx.io on the calculators and calx.com.au in the address bar. Both take you to the same Australian site, which is independent and not affiliated with any government agency, bank or super fund.

• ATO: income tax brackets, Low Income Tax Offset, Seniors and Pensioners Tax Offset, Medicare levy and Medicare Levy Surcharge thresholds, HECS/HELP repayment thresholds, superannuation guarantee rate and concessional caps. See the full tables on the tax rates page.
• State and territory revenue offices: transfer (stamp) duty rates, first home buyer concessions and foreign purchaser surcharges, plus land tax scales, thresholds and absentee owner surcharges for all 8 jurisdictions. Each result on the stamp duty and land tax calculators links to the official source.
• APRA guidance: the 3 percentage point serviceability buffer lenders are required to apply when assessing home loans (APRA is the banking regulator).
• Household Expenditure Measure (HEM): the industry benchmark for minimum living expenses, scaled by household type, dependants and income, as lenders do.
• ASFA Retirement Standard: the benchmark annual budgets for a comfortable retirement used by the super calculator (ASFA is the super industry association).

Rates and thresholds were last refreshed in July 2026. Where the ATO has not yet published next year's indexed thresholds, the prior year's values are carried forward and flagged on the tax rates page.

The pay calculator and tax tracker share the same tax data and core tax calculations (brackets, LITO, HECS/HELP bands and Medicare Levy Surcharge tiers) but run separate calculation flows suited to their inputs. Both work on annual figures: gross pay is converted to an annual amount, pre-tax deductions (salary sacrifice, novated lease, work deductions) reduce taxable income, then income tax is applied bracket by bracket for your category (resident, non-resident, working holiday maker, or resident without the tax-free threshold for a second job).

Offsets (LITO, SAPTO, franking credits) reduce the tax payable. The 2% Medicare levy applies to residents, with the low-income phase-in, and the Medicare Levy Surcharge applies above the threshold when you do not hold private hospital cover. HECS/HELP repayments use the marginal system from FY2025-26 (a percentage of income above each threshold) and the flat-rate tables for earlier years, calculated on repayment income: taxable income plus reportable fringe benefits and salary-sacrificed super.

Every pay calculator result includes an expandable "How this is calculated" breakdown so you can audit each step.

The pay calculator can run the question the other way round: tell it the take-home pay you want and it works out the salary that produces it. This is the same calculation described above, searched rather than read forward. Nothing about the tax rules changes, and no second set of tax logic exists.

Every other input is held exactly as you have set it: financial year, whether super is included in your salary, student debt, Medicare and private hospital cover, salary sacrifice, deductions, novated lease and family settings. Only the salary is varied. The salary the search settles on is then run through the normal calculator one more time, and every figure shown comes from that run, so the answer is never the amount you typed reflected back at you. The result always shows what you asked for, what the salary actually takes home, and the difference between them.

Salaries are solved to the nearest dollar, or the nearest cent for a day or hourly rate, so the take-home usually lands within about a dollar a year of the target rather than exactly on it. When it does not land exactly the result is labelled a closest estimate.

Take-home pay does not always rise smoothly with salary. In the years where HECS/HELP is charged as a flat percentage of your whole repayment income (2024-25 and earlier), and in 2021-22 where the low and middle income tax offset ended at a fixed income, crossing the threshold costs a lump of tax at once. That means two different salaries can produce the same take-home pay. Where that happens both are shown, with the rule that causes it named, and neither is presented as the better answer.

The Medicare levy surcharge steps in the same way, but it is assessed through your tax return rather than withheld from each pay, so the pay calculator reports it separately and does not subtract it from take-home pay. It therefore does not affect the salary solved for here.

The result is an estimate of the salary that produces a take-home figure under these rules. It is not a payroll determination, and an employer's own withholding, pay cycle rounding and package structure can differ.

The tax return tracker estimates a full-year position rather than a pay packet, for the 2022-23 year onwards. It adds the income types an individual return reports (salary and wages, interest, dividends, rental, capital gains, business, trust and foreign income) and subtracts the deductions you itemise, then applies the same brackets, offsets, Medicare levy and HECS/HELP rules as the pay calculator. Franked dividends are grossed up by their franking credits into assessable income before the credits are applied as a refundable offset, and the optional 50% capital gains discount applies to assets held more than twelve months.

It is an estimate to help you prepare, not a lodgement. It does not connect to myGov, does not pre-fill from the ATO, and does not lodge anything. Figures follow ATO individual tax return guidance for the year you select.

The HECS/HELP calculator projects year by year when a debt is cleared, following the ATO's real crediting order rather than a simple balance reduction: voluntary repayments made before 1 June come off first, then indexation is applied to the remaining balance on 1 June, then the year's compulsory repayment is credited when your return is assessed. Amounts withheld from your pay during the year do not reduce the balance until then, which is why a debt can grow in a year you were paying it down.

Compulsory repayments use the same ATO repayment bands as the pay calculator, capped at the remaining debt. Indexation defaults to 2.8%, the rate applied on 1 June 2026, which is set as the lower of CPI and the Wage Price Index; you can change it, and repayment thresholds are indexed forward with the salary growth assumption because they track average weekly earnings. The one-off 20% debt reduction of June 2025 is not applied, because it is already reflected in the balance the ATO shows you.

The shift and penalty rates calculator turns an hourly rate and a weekly roster into an annual gross: each shift type (ordinary, evening or night, Saturday, Sunday, public holiday) is paid at the base rate plus its penalty loading, with casual loading added on top for casuals, the additive approach most modern awards use. The annualised gross then runs through the same tax engine as the pay calculator. Penalty loadings vary by award and are entered by you; the calculator links to the Fair Work pay calculator for authoritative award rates rather than modelling the awards themselves.

The pay rise calculator and the job and pay comparison calculator add no tax rules of their own. Each runs the full pay engine once per scenario and reports the difference, so a comparison is always two complete take-home calculations rather than an estimate applied to a gap. That is why a rise can cross a tax bracket without the result ever showing a fall in take-home pay.

Both assume a resident who claims the tax-free threshold and holds private hospital cover unless you change those settings, and the pay rise calculator uses the current financial year. Employer super, Medicare and HECS/HELP are recalculated in each scenario rather than held constant.

The novated lease calculator runs the pay engine twice, with and without the lease, instead of multiplying the lease cost by a marginal rate. That matters when the packaged amount crosses a tax bracket, where the shortcut overstates the saving.

When you enter the car's value, fringe benefits tax is modelled the way providers structure packages. Petrol and diesel cars use the employee contribution method: the statutory 20% of the car's base value is paid from after-tax salary to cancel the FBT liability, and only the remainder is packaged before tax. Eligible electric cars are exempt from FBT and stay fully pre-tax, but the reportable fringe benefits amount (the taxable value grossed up by 1.8868 once it exceeds $2,000) is still counted as income for HECS/HELP repayments and the Medicare Levy Surcharge. Without a car value, a petrol or diesel result is labelled as a before-FBT estimate. Rates follow the ATO's FBT guidance and the electric car exemption.

The redundancy calculator applies the National Employment Standards weeks scale at your base rate, then the ATO's genuine redundancy rules: the indexed tax-free amount (a base plus an amount per completed year of service), ETP tax on the excess at the concessional rates up to the ETP cap, and flat 32% withholding on unused annual and long service leave. It models a genuine redundancy only: using your date of birth and termination date it checks the ATO condition that you are under Age Pension age on the day of dismissal, and blocks the result with an explanation when you are not, because non-genuine payments depend on your other income (the whole-of-income cap). The 17% concessional ETP rate applies when you reach preservation age by 30 June of the payment year. Figures are verified against ATO withholding schedules 7 and 11 and Fair Work guidance.

Notice is a separate entitlement from redundancy pay, and the calculator keeps the two apart. Under the National Employment Standards the minimum employer notice is 1 week for not more than 1 year of continuous service, 2 weeks for more than 1 and up to 3 years, 3 weeks for more than 3 and up to 5, and 4 weeks beyond that, with one extra week where you are over 45 years old and have completed at least 2 years of service when notice is given. Exactly 45 is not over 45, and that extra week increases notice only: it never changes the redundancy pay weeks. Because the service bands use "more than" boundaries while the calculator holds completed whole years, a result at 1, 3 or 5 years is labelled as estimated, and you can enter your own total notice entitlement from an award, agreement or contract instead. Age is tested on the day notice was given, so where that may differ from your termination date the calculator says so and lets you enter the notice date. Source: Fair Work Act 2009 s 117 and Fair Work Ombudsman, "Notice of termination and redundancy pay".

Payment in lieu of notice is shown as a gross figure and is deliberately excluded from the estimated tax and net payout. Whether it is taxed as part of a genuine redundancy payment depends on whether the amount exceeds what you would have been paid on a voluntary termination, which turns on your own employment terms. Rather than guess, the calculator reports the gross amount and says the treatment depends on your circumstances.

Years of continuous service is your figure, not an assumed one: it drives both the weeks payable and the tax-free limit, so the calculator shows no result until you enter it. When you have not given both a date of birth and a termination date, the Age Pension condition cannot be checked, so the tax-free amount is shown as assumed rather than confirmed until you confirm it.

Long service leave is state law, not federal, so the calculator holds a separate rule set for each state and territory, taken from that jurisdiction's own authority and linked on every result. The rules that differ most are the accrual rate (most states accrue about 0.867 weeks per year of service, South Australia and the Northern Territory 1.3), when the full entitlement arrives (10 years in most states, 7 in Victoria and the ACT), and when a pro-rata entitlement can be paid out on leaving (from 5 years in NSW and the ACT, 7 elsewhere).

Leave accrues from your first day everywhere; the thresholds control access to it, not whether it builds up. Some states pay pro-rata leave on resignation for any reason, others only for specific reasons such as illness or redundancy, and the calculator states which applies rather than assuming. Portable schemes for construction, cleaning and community services (QLeave, CoINVEST and equivalents) follow separate rules and are not modelled. Where your ordinary pay is not simply salary divided by 52, you can enter a weekly figure directly.

The borrowing power calculator works the way lenders assess serviceability, not on rules of thumb. Salaries are converted to after-tax (net) income using the same ATO tax engine. Bonus, overtime, rental and other income are taxed at the marginal rate and then counted at 80%, as lenders do. HECS/HELP repayments are estimated from each applicant's income at ATO rates, not as a flat percentage of the balance.

Living expenses use the higher of your declared figure and a HEM benchmark scaled by household type, dependants and income. Credit cards are assessed at 3.8% of the limit per month. The loan is then sized with a principal-and-interest annuity formula at your rate plus the 3 percentage point APRA buffer. Deposit, loan-to-value ratio (LVR), an indicative lenders mortgage insurance (LMI) estimate and a maximum purchase price are derived from your savings, capped at 95% LVR.

Repayments compound at the frequency you choose (weekly, fortnightly or monthly). Extra repayments and offset balances are modelled with a period-by-period simulation of the full schedule rather than a closed-form formula, so their effect on interest and payoff time is exact for the assumptions given. Interest-only periods revert to principal-and-interest for the remaining term. Savings are measured against a clean baseline schedule with no extras and no offset.

Transfer duty uses each state and territory's published rate tables, including owner-occupier rates (VIC, QLD, WA), first home buyer exemptions and concessions, foreign purchaser surcharges, and the NT's quadratic formula. Victoria's pensioner concession is calculated; for other states the calculator shows a reminder to check the revenue office because eligibility rules vary too much to model reliably. Concession tapers (such as NSW between $800,000 and $1,000,000) are linear approximations of the official scales and are flagged as such in the results.

Land tax uses each state and territory's published progressive rate scale, applied to the total taxable land (site) value you enter, the same aggregated basis the state revenue offices assess on. Separate company and trust scales are applied where they exist (VIC trust surcharge rates, QLD companies and trustees, SA trusts, NSW special trusts), along with foreign and absentee owner surcharges and WA's metropolitan region improvement tax. The ACT is the exception: it assesses each property separately, as a fixed charge plus marginal rates on that property's average unimproved value (AUV, the average of up to the last 5 years of unimproved values), so enter one property's AUV and calculate each ACT rental separately. The Northern Territory levies no land tax. Exemptions (your own home, primary production) are excluded by entering only taxable land value.

The super calculator projects your balance year by year to retirement: employer contributions at the super guarantee rate plus any salary sacrifice, less 15% contributions tax, with investment returns, fees, inflation and salary growth applied annually. Results are shown in both nominal dollars and today's dollars. Retirement income is estimated with a real-return drawdown to age 90 and compared against the ASFA comfortable standard.

The capital gains calculator covers one disposal by an Australian resident individual of shares, ETFs, managed funds, crypto or another investment asset. It works out the capital proceeds and the cost base, applies your capital losses, then applies the 50% discount to what is left. Property is deliberately excluded: the main residence exemption, the six-year absence rule, partial rental use, market value when a home first earns income and capital works adjustments change the answer too much for a general figure to be useful.

The order matters and is the part people most often get wrong. Current-year capital losses come off first, then losses carried forward from earlier years, and only then is the remaining gain halved. Applying the discount first would understate the gain. A capital loss can only reduce capital gains, never salary or other income, and anything unused carries forward.

The 50% discount needs the asset to have been acquired at least 12 months before the capital gains tax event. The ATO counts that period excluding both the day of acquisition and the day of the event, so an asset bought on 20 June and sold on 20 June the following year is one day short. Both dates are contract dates, not settlement dates, and the sale contract date is what decides which financial year the gain falls in.

The cost base has five elements: what you paid, the incidental costs of buying and selling, non-deductible costs of owning the asset, capital improvements, and costs of establishing or defending title. The third of those is left out when working out a capital loss, which is why proceeds can occasionally land between the two figures and produce neither a gain nor a loss. Cost base reductions, such as a tax-deferred amount shown on a managed fund statement, lower the cost base and so raise the gain.

Capital gains tax is not a separate tax and there is no capital gains tax rate. The estimated additional tax is produced by running the same annual tax calculation twice, once without the net capital gain and once with it, changing nothing else. The difference is reported as income tax, Medicare levy, Medicare levy surcharge and study loan repayment, because a gain can move all four. Your actual position depends on your complete return.

Sales from 1 July 2027 are not estimated. For gains accruing from that date the 50% discount for individuals, trusts and partnerships is replaced by cost base indexation and a minimum 30% tax on real gains, which is already law. A figure worked out under the old rules would be wrong, so the calculator says so instead of showing one.

Savings and investment growth is simulated period by period rather than with a closed-form formula, so fees and contribution timing stay exact and the year-by-year table cannot disagree with the headline. The annual return you enter is converted to a true equivalent periodic rate, which means a 6% assumption grows a starting balance by exactly 6% over a year whether you contribute weekly, fortnightly, monthly or annually. Fees reduce the return rather than being taken as a separate amount, so a 6% return with 1% fees compounds at 5%. That is a simple subtraction of the two annual percentages: a fee deducted from the balance each period would cost a little more, so the fee treatment is a close approximation rather than an exact model of how a fund charges. Inflation is applied only to produce the today's dollars figure, never to the projected balance itself.

Returns are assumed constant and smooth, which no real investment is, and no tax is modelled: income tax on interest and dividends, capital gains tax and franking credits all depend on circumstances this calculator does not ask for. Superannuation is taxed differently again and is projected separately.

• All results are estimates based on the inputs you provide. They are not financial, tax or credit advice.
• The pay calculator models annual tax liability. Actual PAYG withholding from each payslip follows ATO withholding schedules and can differ slightly, with the difference settled at tax return time.
• Family (combined) thresholds for the Medicare levy and the Medicare Levy Surcharge are modelled once you enter a spouse's taxable income or dependent children. Seniors and Pensioners Tax Offset family thresholds, and a spouse's own reportable super or fringe benefits, are not.
• Lender policies differ. Real borrowing power depends on how much of your variable income a lender counts, how it treats expenses, and its credit policy. LMI premiums are banded estimates.
• Stamp duty concession tapers are linear approximations, and eligibility rules (residence periods, caps, income tests) are simplified. Always confirm with the state revenue office.
• Land tax grouping, joint ownership and secondary deduction rules, special exemptions, and surcharge edge cases are not modelled; the calculator assesses the single aggregated land value you enter.
• Super projections depend heavily on assumed returns, fees and inflation; small changes compound over decades.
• Where next year's indexed thresholds are not yet published by the ATO, prior year values are carried forward and flagged.

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