This simple tax calculator is modelled after the ATO simple Tax Calculator. It does not include Medicare Levy and Surcharges. Low income tax offset is also not part of the calculator. It will give you a rough guide as to what tax liability is based on the individual total income for the year.
You will see three different tabs; one for each financial year. Click on the tab (financial year) that is relevant for your purposes. It will bring up the sheet with tax rates for that year. Just enter your taxable income and it will calculate your tax payable for that year.