All you need to do is input your annual gross income, select the tax year you want to calculate your liability for and click 'Calculate'. The app will then break down the tax you're paying (or have
paid) at each of the Pay As You Earn (PAYE) tax bands and in respect of ACC levies. It will also display your net (i.e. after tax) income and your effective tax rate (i.e. tax paid divided by your
annual gross income).
Note: this app is for indicative purposes only. You should consult a tax advisor for a full and accurate assessment.