Time Duration & Hours Worked Timesheet Calculator

Clock span minus a break equals net worked hours

A 9:00 AM start to a 5:30 PM end spans 510 minutes (8.5 hours) on the clock. Subtracting a 30-minute unpaid break leaves 480 net minutes, or exactly 8.00 hours worked.

This distinction between clock span (510 minutes, the raw time between clock-in and clock-out) and net minutes (480, what actually gets paid) matters for timesheet accuracy -- an employee working a standard 8-hour day with a 30-minute unpaid lunch actually needs to be on the clock for 8.5 hours total, not exactly 8, to net out to a genuine 8-hour paid day.

480 minutes converting to exactly 8.00 hours (480 / 60 = 8) is a clean result specifically because the numbers in this example line up evenly -- a shift with an odd number of minutes worked would produce a decimal hour value (like 7.75 or 8.25) rather than a round number.

How this handles an overnight shift

Overnight is assumed when end is earlier than start. Not a payroll export. If the end time entered is earlier than the start time (like a 10:00 PM start and a 6:00 AM end), the calculator assumes the shift crosses midnight into the next day, rather than treating it as a negative or invalid duration -- a necessary assumption for correctly calculating night-shift hours.

This is a single-shift calculation -- it doesn't accumulate multiple shifts across a pay period into a weekly or biweekly total, which would require entering and summing each shift's net hours separately outside this tool.

The unpaid break field assumes exactly one break subtracted from the total span -- a shift with multiple separate breaks (a morning break plus a lunch break, for example) would need those combined into one total break-minutes figure before entering it here.

Related time and payroll-adjacent tools

For converting the resulting decimal hours into a format some payroll systems expect (like converting minutes past the hour into a clean decimal), the Time to Decimal Hours Converter handles that specific conversion.

For adding or subtracting two separate time durations (rather than calculating one shift's net hours), the Time Adder/Subtractor is the related tool.

Frequently Asked Questions (FAQ)