Calculate actual working hours per week.
Contracted hours are not worked hours. Unpaid breaks come out first — a 45 minute lunch across five days is nearly four hours a week, so a nominal 40-hour contract is closer to 36 of actual work. Annual leave and public holidays then reduce the weeks worked, converted from days at your own working pattern so a part-time week is handled correctly. The annual figure is what to divide a salary by if you want a genuine hourly rate.
Net week
Net weekly hours = contracted hours - unpaid break minutes x working days / 60
Annual
Weeks worked = 52 - (leave days + public holidays) / working days per week; annual hours = net weekly x weeks worked
No — only unpaid ones. If your employer pays through a short break, it is part of your contracted hours and belongs in the total rather than out of it.
Because dividing salary by 52 times contracted hours overstates the hours and understates the rate. Using hours actually worked typically raises the calculated rate by 15 to 20 percent.