This New Zealand calculator works out the value of shift allowances and penal rates on top of your base pay. Whether your extra is a fixed amount per shift or a penal multiplier such as time and a quarter for nights or weekends, this tool shows what those shifts add to your weekly and yearly earnings. It helps you see the true value of unsociable hours when weighing up a roster or a job.
Shows the extra above your base rate. Allowances and penal rates are taxable through PAYE, so the after-tax value is lower. Check your employment agreement for the exact rates. Estimate only.
The calculator takes the extra above your base rate from the penal multiplier on your shift hours, plus any fixed per-shift allowance across your shifts, to give the weekly extra and the yearly total. It also shows your effective hourly rate while on shift, so you can see what the unsociable hours are really worth before tax.
On a $28 base rate, 20 hours a week at a 1.25x penal rate adds 0.25 x $28 x 20, about $140 a week or roughly $7,280 a year, lifting your effective shift rate to $35 an hour.
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