No details of the amounts that you enter or the calculated figures are saved in the Tax Calculator app or by Kinphar. Information will only leave the app if you choose to send the pay calculation details using the sharing option.

Primary Income is when you have advised your employer that you wish to claim the Tax Free Threshold from this employer - it is a question that you answer when completing the Tax File Number Declaration. Set to calculate tax on a secondary income when you have two or more jobs with different employers and you are not claiming the Tax Free Threshold from this employer. Secondary income will show a higher withholding amount than Primary income.

Select the pay frequency and enter your taxable income. If a different pay frequency is then selected, the income shown will re-adjust eg if you enter an annual income of $60,000 and then select monthly, the income figure will read $5,000.

To most closely match details on your pay advice, it is suggested that you enter the income amounts on the frequency that you get paid eg if you are paid fortnightly then enter your fortnightly pay. From there you can then see the equivalent amount expressed on a weekly, monthly or annual basis.

To the left of the income figure there is a settings icon. Tap on this icon and the options are displayed allowing the selection of Main or Secondary Income as well as indicating if you have a HELP/TSL and/or SFSS repayment due. For Main Income/Secondary Income, as one is set on the other will automatically turn off.

PAYG stands for Pay As You Go and is the amount of income tax and Medicare Levy that an employer must withhold from your income when you are paid.

HELP is the Higher Education Loan Program and TSL is a Trade Support Loan. If you have either of these loan types from the government then set the HELP/TSL option on in setting to ensure that repayment of these loans is added to the tax calculation.

SFSS is the Student Financial Supplement Scheme. If you have a SFSS debt due to the government then set the SFSS option on in settings to ensure that repayment of this loan is added to the tax calculation.

The calculation of superannuation payable by an employer is subject to weekly, monthly and quarterly thresholds and is calculated on Ordinary Time Earnings which may be different from the income on which tax is calculated (eg an employer does not have to pay superannuation on overtime). Without a detailed breakdown on the timing and type of income you are receiving, no meaningful calculation of superannuation can be made.

The ATO calculates PAYG and HELP/TSL or PAYG and SFSS or PAYG and HELP/TSL and SFSS as one calculation. In the Kinphar tax calculator, PAYG, HELP/TSL and SFSS are all calculated as separate figures. This can lead to occasional rounding differences. The ATO also publishes some separate data for HELP/TSL and SFSS and these figures should match those calculated by the Kinphar tax calculator.

The Kinphar tax calculator assumes that there are 12 months, 26 fortnights and 52 weeks in a year.

In some years there can be 27 fortnightly pay dates and 53 weekly pay dates. This can lead to differences in totals. When this occurs, your employer may also have made adjustments to the PAYG amount to account for the additional pay period in the year which can cause a difference to the figure shown in the calculator.

When you are paid weekly of fortnightly, the monthly figure is for guidance only and is unlikely to reflect the actual amount you have been paid.