Daily working-capacity cells across partial and full ISO weeksLive current inputs
Date & Time
Week Number Business-Day Calculator
Convert an inclusive ISO week range into auditable working-day capacity, including partial boundary weeks, selected workdays, holidays, shutdown days, and a protected close reserve.
Inclusive calendar span—
ISO weeks touched—
Scheduled working days—
Net working days—
Execution days after reserve—
Unavailable scheduled share—
Inclusive ending point—
Boundary validity—
ISO business-day mosaic
Daily working-capacity cells across partial and full ISO weeks
Every cell represents one calendar day. Workdays, weekends, holidays, shutdown allocation, and close reserve remain visually distinct across the year seam.
ISO-week capacity register
Scheduled, unavailable, reserved, and executable days by week
The register preserves partial first and last weeks instead of rounding the interval to whole weeks.
| ISO week | Days in span | Scheduled | Holiday/shutdown | Close reserve | Executable | Week status |
|---|
Calendar range setup
Describe both ISO boundaries precisely
- Use ISO week-year values, not calendar-year assumptions.
- Enter the weekday inside each boundary week.
- Set the organization's normal scheduled workdays.
- Count only holidays and shutdowns that remove scheduled days.
- Reserve close days after unavailable days are deducted.
Inclusive-day logic
Partial weeks can materially change capacity
A Wednesday start and Friday end include different working-day counts than a whole-week approximation, even when the number of week labels is unchanged.
Exception days are spread through the eligible week buckets for planning visibility. When exact holiday dates matter, replace the allocation with a date-level corporate calendar.
Calculation method
Count real included weekdays before subtracting exceptions
The start and end ISO labels are converted to Monday-based dates. The model counts only included weekdays allowed by the work pattern, then allocates entered holidays, shutdowns, and close reserve without double subtraction.
Detailed calculation process and general formulas
d_0 = ISODate(Y_s, W_s, u_s); d_1 = ISODate(Y_e, W_e, u_e)D = max(d_1 - d_0 + 1, 0)S = sum(d=d_0..d_1) 1[weekday(d) <= w]N = max(S - H - X, 0)E = max(N - R, 0)Symbols, meanings, and units
- D
- inclusive calendar spancalendar days
- w
- scheduled weekdays at the start of each ISO weekdays/week
- H
- holidays that remove scheduled working daysdays
- X
- additional shutdown daysdays
- R
- net working days protected for close activitiesdays
Capacity layers
Separate calendar presence from executable supply
The model removes four distinct layers from the visible interval.
Calendar envelope
—Every included day from the starting weekday through the ending weekday.
Contracted supply
—Included days that match the weekly work pattern.
Net attendance
—Scheduled days after holidays and shutdowns.
Execution runway
—Net days remaining after close reserve.
Decision takeaway: Promise work from executable days, not from week labels or calendar-day totals.
Calendar controls
Avoid the common double-counts
- Do not subtract a holiday that falls on an unscheduled day.
- Do not count shutdown days again as close reserve.
- Confirm week 53 exists in the chosen year.
- Keep the end weekday inclusive if that matches the commitment.
Business-calendar evidence
Inputs to source before using the result
- ISO calendar export
- Employee workweek policy
- Holiday and plant-shutdown list
- Quarter-close checklist
- Delivery commitment record
Practical applications
Decisions this calculator is designed to support
Year-end implementation window
A team starts Wednesday of ISO week 49 and must finish Friday of week 06 after holiday closures.
What the result clarifies: The mosaic makes partial boundary weeks and the year seam auditable.
Regulatory close window
A reporting team protects three final working days for sign-off rather than production.
What the result clarifies: The executable count prevents close reserve from being sold as delivery capacity.
Worked example
Current-input substitution and reconciliation
Model limitations
Holiday and shutdown days are allocated to eligible weekly buckets because individual exception dates are not entered. The result is a planning estimate, not a payroll, legal, or settlement calendar.
Week Number Business-Day Calculator FAQ
Are the start and end weekdays included?
Yes, both boundary days are included when the end point is not earlier than the start point.
Can week 01 belong to dates in December?
Yes. ISO week-years follow the Thursday rule and can begin before January 1.
Why protect close reserve after holidays?
Close reserve is planned work capacity, while holidays and shutdowns are unavailable capacity.
What if the entered end precedes the start?
The page reports an invalid boundary and returns zero executable capacity.