Working Days Calculator (Factory Workweek Schedule)
Calculate actual working days available for production between target dates based on your factory weekly schedule.
That distinction matters because factory capacity is planned in working days, not calendar days. A line that sews 900 pieces on each working day produces nothing on its weekly day off, so a delivery plan built on calendar days overstates what the floor can actually finish. This calculator uses the factory weekly schedule you select, with the 6-day Monday to Saturday pattern as the default, because that is the standard schedule in garment factories. Both the start date and the end date are counted, so a single-day range returns one day, not zero.
What is Working Days Calculation?
A working day is any day the factory is scheduled to run under its weekly pattern. A weekend non-working day is a day the pattern marks as off: Saturday and Sunday on a 5-day schedule, Sunday only on a 6-day schedule, and no day at all on a 7-day continuous schedule. The total calendar span is the full count of days from the start date to the end date, both ends included, so working days plus weekend non-working days always add up to the total calendar span.
Planners use working days as the denominator for everything downstream: line capacity, shipment windows, and labour plans all divide by working days, not calendar days. If a plan assumes 28 days of production in a 4-week window but the factory runs a 6-day week, only 24 of those days actually produce. Counting working days first prevents that shortfall from appearing as a missed shipment later. If you need a target date rather than a day count, use the Calendar Days Calculator.
Formula
Total calendar days = Count of dates from start date to end date, both ends included Working days = Total calendar days minus weekend non-working days 5-day schedule: weekend days = Saturdays + Sundays 6-day schedule: weekend days = Sundays only 7-day schedule: weekend days = 0
- Start date: first date of the range, counted as a working or weekend day according to its weekday.
- End date: last date of the range, counted the same way. The tool requires the end date to be on or after the start date.
- Factory schedule: the weekly pattern, 5 days (Monday to Friday), 6 days (Monday to Saturday), or 7 days (continuous).
- Working days: the result used for capacity planning, the days the factory is scheduled to run.
- Weekend non-working days: days in the range that fall on the scheduled weekly day off.
- Total calendar days: the full inclusive span, shown so the split can be checked.
How to Calculate
- Enter the start date of the production window.
- Enter the end date. The end date must be on or after the start date.
- Select the factory schedule: 6 days per week for the standard garment factory pattern, 5 days for a Monday to Friday operation, or 7 days for continuous running.
- Read the three results: net working days, weekend non-working days, and total calendar days. Check that working days plus weekend days equal the total.
- Subtract public holidays and any planned shutdown days separately, because this tool applies only the weekly pattern and does not know factory holidays. Use the remaining working days for capacity and shipment planning, for example with the Lead Time Calculator.
Example
Take an illustrative four-week window from Monday 2 November 2026 to Sunday 29 November 2026. The total calendar span is 28 days. On the default 6-day schedule the four Sundays (8, 15, 22 and 29 November) are non-working, giving 24 working days and 4 weekend days. On a 5-day schedule the four Saturdays and four Sundays are non-working, giving 20 working days and 8 weekend days. On a 7-day continuous schedule all 28 days count as working days.
The planning consequence is direct. An order needing 24 working days fits exactly into this window on a 6-day schedule, finishing on 29 November. On a 5-day schedule the same 24 working days are only reached on Thursday 3 December, four calendar days later. A plan written in calendar days would miss that gap entirely, which is why the working-day count comes before any capacity or shipment promise. The same logic scales down: a single week from Monday 2 November to Sunday 8 November gives 6 working days on a 6-day schedule and 5 on a 5-day schedule, from the same 7 calendar days.
Assumptions
This calculation applies one weekly pattern uniformly across the whole range, counts both endpoints, and recognises no public holidays, festival closures, overtime days, or unplanned shutdowns. If the factory closes for a holiday inside the range, subtract that day from the working-day result by hand. The schedule is chosen once for the whole range, so a mid-range schedule change must be calculated as two separate ranges. Results are whole days only: the tool does not split a day into hours, so a half-day working pattern should be handled outside the calculator.