Handle shift length, break deductions, overtime, night shifts, rota totals, and part-time percentages.
In the UK, unpaid lunch breaks normally only come out of paid time when you are genuinely relieved from work, average weekly hours are usually checked over a longer reference period, and overtime premiums often come from the contract rather than one universal statutory rate.
If your workplace uses paid breaks, on-call time, or shift differentials, compare the calculator result with your rota rule before treating the number as payroll-ready.