Australia calculators handle the parts of everyday math that are specific to Australia: 10% GST, superannuation, home loan repayments, the July to June financial year, state-by-state daylight saving and Australian spoons. These free Australia calculators cover money, pay, school and units, and show the working for every result.
Quick answer: Australian GST is 10%, so $110 including GST contains $10 of GST and $100 plus GST is $110. Employers must pay super at 12% of qualifying earnings, so an $80,000 salary earns $9,600 of super. Daylight saving applies in New South Wales, Victoria, Tasmania, the ACT and South Australia, but not Queensland, Western Australia or the Northern Territory.
How to use these Australia calculators
Each of the Australia calculators opens with a worked example, so you see an answer before you type. Choose Australia in tools that have a country setting and set the currency to dollars, and the rates and rules switch for you.
- Choose the calculator from the decision table below or the cards above.
- Select Australia in the country box, and use the dollar symbol for A$.
- Type your numbers. Rates such as a home loan rate are editable examples, not quotes.
- Read the answer, open the working, then copy the result or the link.
Everything runs in your browser and nothing is sent to a server, so the Australia calculators are safe for pay and loan figures. Results are estimates for planning, not tax or financial advice.
Which Australia calculator do I need? A quick decision table
This table matches common Australian questions to the right tool among the Australia calculators. The link text names each one, so you can scan for your own question and open the Australian calculator that fits it.
| If you want to… | Use this calculator |
|---|---|
| Add or remove 10% GST | GST calculator |
| Estimate a home loan repayment | Mortgage calculator |
| Compare personal loan or car loan repayments | Loan calculator or Car loan calculator |
| Project super and savings against inflation | Retirement calculator |
| See how savings grow with regular deposits | Compound interest calculator |
| Turn an hourly rate into a yearly wage | Hourly to salary calculator |
| Test overtime or penalty rate loadings | Overtime calculator |
| Add up hours and breaks on a roster | Work hours calculator |
| Work out a weighted grade or a final exam mark | Weighted grade calculator or Final grade calculator |
| Check BMI in kilograms and centimeters | BMI calculator |
| Convert cups, spoons and oven temperatures | Cups to grams converter or Temperature converter |
| Convert liters per 100 km and kilometers | MPG calculator |
| Plan a call across Sydney, Perth and Auckland | Time zone converter |
| Count working days around public holidays | Business days calculator |
| Estimate paint, concrete or flooring in square meters | Paint calculator, Concrete calculator or Flooring calculator |
GST calculator Australia: 10% and the New Zealand 15%
GST is a tax of 10% on most goods, services and other items sold or consumed in Australia, according to business.gov.au. A business must register for GST when its GST turnover is $75,000 or more, or $150,000 for a non-profit. The GST calculator adds or removes GST in one step and shows the working.
| Question | Working | Answer |
|---|---|---|
| Add GST to $100 | $100 × 1.10 | $110.00 ($10.00 GST) |
| Remove GST from $110 | $110 ÷ 1.10 | $100.00 ($10.00 GST) |
| GST inside any total | total ÷ 11 | $220 contains $20 |
| New Zealand: add 15% GST to $100 | $100 × 1.15 | $115.00 ($15.00 GST) |
| New Zealand: GST inside $115 | $115 × 3 ÷ 23 | $15.00 |
The shortcut for Australia is to divide a GST-inclusive price by 11, because the GST is one eleventh of the total. New Zealand charges 15%, according to Inland Revenue, so its GST is 3 twenty-thirds of a GST-inclusive price.
Australia and New Zealand calculators: what changes
The Australia calculators share formulas with the rest of the site, but several defaults are local. New Zealand sits beside Australia in many searches, so the table shows both. Always confirm a rate with the Australian Taxation Office or Inland Revenue before an invoice or a return.
| Topic | Australia | New Zealand |
|---|---|---|
| GST rate | 10% | 15% |
| Retirement savings | Superannuation, 12% employer rate | KiwiSaver |
| Financial year | 1 July to 30 June | 1 April to 31 March |
| Daylight saving | NSW, Vic, Tas, ACT and SA only | Last Sunday in September to first Sunday in April |
| Tablespoon | 20 mL | 15 mL |
Australian financial calculators: home loans, personal loans and savings
Australian financial calculators use the same formulas as everywhere else, so the key is the country setting and a realistic rate. The mortgage calculator shows principal and interest repayments, and Australian lenders offer monthly, fortnightly or weekly repayments over terms up to 30 years. The loan calculator and car loan calculator compare personal and car loans, and the compound interest calculator projects savings with regular deposits.
Example: an A$800,000 home with a 20% deposit is a $640,000 loan. At 6.2% over 30 years the repayment is $3,919.80 a month and total interest is $771,128. Paying half of that amount every fortnight makes 26 payments a year, equal to 13 monthly payments, which clears the loan in about 24 years 5 months and cuts interest to $601,048.
With a deposit under 20%, a lender may charge lenders mortgage insurance (LMI), and an offset account can cut the interest you pay because the balance in it is netted against the loan. Moneysmart, the Australian Government money guide, has its own mortgage calculator and explains both.
Retirement calculators Australia: superannuation at 12%
Retirement calculators Australia users need start with super. According to Moneysmart, employers must usually pay super to workers aged 18 or over at 12% of qualifying earnings, which include commissions, overtime and irregular payments. On an $80,000 salary that is $9,600 a year. You can usually access super at age 60 if you change employers or retire, or at age 65 whether you are working or not. The retirement calculator treats your super balance as savings and the Age Pension, if you qualify, as other income.
The concessional contribution cap is $32,500 a year, according to Moneysmart, and it includes your employer’s super guarantee and any salary sacrificed amount. Contributions are taxed at 15%, which can be lower than your marginal rate. The limit can change each financial year, so confirm it with the Australian Taxation Office.
Income tax examples for Australian residents, 2026 to 2027
These Australian financial calculators do not file a return, but the rates help with planning. The Australian financial year runs from 1 July to 30 June. For residents in 2026 to 2027, Moneysmart lists income up to $18,200 as nil tax, 15 cents per dollar from $18,201 to $45,000, $4,020 plus 30 cents from $45,001 to $135,000, and $31,020 plus 37 cents from $135,001 to $190,000, with higher rates above that. The 2% Medicare levy is extra.
| Taxable income | Income tax, before Medicare levy and offsets | Average rate |
|---|---|---|
| $18,200 | $0 | 0% |
| $45,000 | $4,020 | 8.9% |
| $80,000 | $14,520 | 18.1% |
| $135,000 | $31,020 | 23% |
| $190,000 | $51,370 | 27% |
Car loans work the same way. A $35,000 loan at 7% over 5 years costs $693.04 a month, and the car loan calculator shows the total interest of $6,583. Compare the repayment with the balloon, if your lender offers one, and with the comparison rate, which includes fees.
Pay, overtime and penalty rates in Australia
Australian pay rates, hours and loadings are set by awards and agreements, which the Fair Work Commission publishes, and many workers are paid a base rate plus penalty rates. A straight hourly to salary conversion is a baseline, not the full picture, and the Australia calculators let you add loadings separately. At $30 an hour for 38 hours a week for 52 weeks, the yearly wage is $59,280. Use the hourly to salary calculator for the baseline and the overtime calculator with the multiplier from your own award.
Grades and ATAR in Australia
Many Australian universities use bands such as High Distinction at 80 to 100, Distinction at 70 to 79, Credit at 60 to 69, Pass at 50 to 59 and a fail below 50, though some set the High Distinction line higher. The ATAR is a rank reported up to 99.95, not a percentage mark. The weighted grade calculator and final grade calculator work with marks and weights from your course outline.
Australian BMI calculator in kilograms and centimeters
An Australian BMI calculator uses metric by default: BMI = kg ÷ m². A person who is 175 cm and 70 kg has a BMI of 70 ÷ 1.75² = 22.9, in the 18.5 to 24.9 range most health services call healthy. BMI is a screen, not a diagnosis. The BMI calculator also takes pounds and inches.
Metric units, cups and the 20 mL Australian tablespoon
Australia is fully metric: kilometers, liters, kilograms and Celsius, and fuel economy in liters per 100 km. In the kitchen, the metric cup is 250 mL, and an Australian tablespoon is 20 mL, which is four teaspoons, while a US tablespoon is 14.79 mL and a metric tablespoon is 15 mL. A recipe asking for 2 tablespoons therefore means 40 mL in Australia, about 20% more than elsewhere. The cups to grams converter and temperature converter handle these.
Dates, daylight saving and public holidays
New South Wales, Victoria, Tasmania, the ACT and South Australia observe daylight saving time, from the first Sunday in October to the first Sunday in April, which is October 4, 2026 to April 4, 2027. Queensland, Western Australia and the Northern Territory do not, and New Zealand runs from September 27, 2026. The time zone converter applies the rules by date. Public holidays are declared state by state, so add your own to the business days calculator. Australian dates are written day, month, year, so check the order each Australia calculator expects.
Real-life uses for Australia calculators
- Invoicing. A $2,500 job plus GST is $2,750, and the GST of $250 goes on the business activity statement.
- Buying a home. Compare fortnightly and monthly repayments on the same loan before you apply.
- Checking super. At 12% on $80,000, $9,600 should reach your fund each year, so compare it with your statement.
- Cooking. A recipe from Australia asking for 3 tablespoons of oil uses 60 mL, not 45 mL.
- Working with Perth. Perth does not change its clocks, so the gap to Sydney is 2 hours in winter and 3 hours during daylight saving.
Australian calculators for students
Australian calculators for students cover school and university. Year 12 students can test marks against the ATAR cut-offs they are aiming for, and university students can work out a weighted grade for a unit with an exam worth 50%. If you have 68% from coursework worth 50% and want 70% overall, the final exam must score 72%, because 0.50 × 68 + 0.50 × 72 = 70. The final grade calculator does that sum for any weights, and the weighted grade calculator prints practice from the math worksheets.
Key terms for Australia calculators
These terms appear across the Australia calculators, so it helps to know what each one means.
| Term | Meaning |
|---|---|
| GST | Goods and services tax, 10% on most goods and services |
| Superannuation (super) | Retirement savings, with employer contributions of 12% of qualifying earnings |
| LMI | Lenders mortgage insurance, often charged when the deposit is under 20% |
| Offset account | A transaction account whose balance is netted against the home loan |
| Financial year | 1 July to 30 June |
| ATAR | Australian Tertiary Admission Rank, reported up to 99.95 |
Questions people ask about Australian calculators
Is there a free online calculators Australia option for GST?
Yes. The GST calculator is free and adds or removes 10% GST in one step. Type the price, choose add or remove, and read the GST amount, the total and the working.
Which Australian calculators cover tax and super?
These pages show GST, super arithmetic and income tax examples. For a tax return or an exact super figure, use the Australian Taxation Office tools, because your result depends on your income, offsets and fund.
What are the best retirement calculators Australia has for super?
Moneysmart offers a government superannuation calculator, and the retirement calculator here lets you test balance, savings, returns and inflation with the working shown. Compare both and check your own fund’s fees.
Frequently asked questions
10 quick answers
What are Australia calculators?
Australia calculators are tools that use Australian rules and units: 10% GST, super at 12%, home loan repayments, the July to June financial year, state-by-state daylight saving and the 20 mL Australian tablespoon. They show the formula and the working.
What is the GST rate in Australia?
Australian GST is 10% on most goods and services, according to business.gov.au. A $100 price becomes $110 with GST, and a $110 price contains $10 of GST, which is one eleventh of the total.
What is the GST rate in New Zealand?
New Zealand GST is 15%, according to Inland Revenue. A $100 price becomes $115, and the GST inside a $115 price is $15.
What is the super guarantee rate?
Employers must usually pay super at 12% of qualifying earnings for workers aged 18 or over, according to Moneysmart. On a $60,000 salary that is $7,200 a year.
How much tax do I pay on $80,000 in Australia?
For a resident in 2026 to 2027, tax on $80,000 is $4,020 plus 30 cents on the $35,000 above $45,000, which is $14,520 before the 2% Medicare levy and any offsets.
What is the tax-free threshold?
The tax-free threshold for Australian residents is $18,200 in 2026 to 2027, according to Moneysmart. Taxable income up to that amount has nil tax, before the Medicare levy.
How much is a $640,000 home loan repayment?
A $640,000 loan at 6.2% over 30 years costs about $3,919.80 a month in principal and interest. Rates are examples, so type your lender’s rate to match a quote.
Which states have daylight saving?
New South Wales, Victoria, Tasmania, the ACT and South Australia observe daylight saving time. Queensland, Western Australia and the Northern Territory do not, so check the state before you schedule a call.
Do the Australia calculators work for New Zealand?
Mostly yes. The GST calculator has a New Zealand 15% setting, the time zone converter knows New Zealand daylight saving, and the unit tools are metric. Check Inland Revenue for New Zealand tax and KiwiSaver rules, which differ from Australia.
Are the 2026 figures current?
GST, super and tax figures were checked in October 2026 against Moneysmart and business.gov.au. Home loan and savings rates are editable examples, and thresholds can change each financial year.
Related calculators and country hubs
- Main hub: all free online calculators
- Other countries: USA calculators, Canada calculators, UK and Europe calculators
- Most used in Australia: GST calculator, mortgage calculator, retirement calculator, percentage calculator
- Practice: money worksheets and measurement worksheets
Sources and further reading
- business.gov.au: register for GST
- Moneysmart: superannuation
- Moneysmart: income tax rates
- Inland Revenue New Zealand: GST
- Moneysmart: mortgage calculator
Last updated: October 2026.