Work planning
How to calculate work hours in a week from a shift schedule
Turn daily start times, finish times, and unpaid breaks into a clear weekly work-hours estimate.
Updated July 30, 2026 · 4 min read
Start with the full daily shift span
For each day, calculate the time between the start and finish. A schedule from 09:00 to 17:30 has a full span of 8 hours and 30 minutes before any break is removed.
This first number is useful because it separates the time you are scheduled to be available from the time that counts as net working time. Keep it visible when you compare different shift patterns.
Subtract unpaid breaks before multiplying
Subtract only the breaks that are unpaid for the purpose of a planning estimate. In the 09:00 to 17:30 example, a 30-minute unpaid break leaves 8 net hours for the day.
If that pattern repeats for five days, multiply 8 net hours by 5 to estimate a 40-hour week. Different start times or break lengths should be calculated day by day before adding them together.
Keep overnight shifts and payroll rules separate
A shift ending after midnight needs to be marked as ending on the next day. Otherwise, a calculator may read the finish time as earlier than the start time on the same date.
The estimate is for planning. Paid breaks, overtime, rounding, holiday work, and attendance rules can change an official total, so use the employer's records when salary or a formal timesheet is involved.