Guides
Spreadsheet and API tools holidays 2027: criteria, no dates
Spreadsheet and API tools holidays 2027: criteria for one closure list in Excel, Sheets, and Nager.Date, versioning it, and why no dates are listed here.
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Guides
Testing an SLA deadline clock: the checks worth running before you trust it
What an SLA deadline clock has to model before any calculator is fit for it: windows, zones, pause rules, clock changes, and four acceptance tests to run.
Guides
Working days per month mistakes: the traps and the way around them
Working days per month mistakes: the average-month divisor, the inclusive month edge, the leap-year February, and other errors that survive review.
Guides
Multiple working calendars in one Excel sheet: WORKDAY.INTL weekend strings
How to hold several working calendars in one Excel sheet: WORKDAY.INTL weekend strings, a calendars and closures table lookup, and what breaks.
Guides
Canada Post delivery standards business days: how they count
Canada Post delivery standards business days start at the acceptance scan. It covers weekends, statutory holidays, local cut-offs and cross-border handover.
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Does Montreal payroll follow Quebec holiday counting under the Civil Code?
Montreal payroll runs on two clocks: Civil Code payment terms between businesses and Quebec labour standards for employees, and holidays move each one differently.
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4 rules for counting Nova Scotia and Newfoundland business days in Halifax and St. John's
Nova Scotia and Newfoundland business day counts need both provincial holiday lists, plus port and offshore calendars that close on days the province is open.
Guides
Ottawa's federal public service calendar for contractors counting business days
Federal public service holidays in Ottawa do not match Ontario's statutory list, and that gap moves contract and SLA deadlines by a day or more.
Guides
Working hours API: the four operations and their responses
A working hours API answers four questions: duration, add, is_open and next_open. Edge rules, a response with segments, and test vectors for each.
Guides
How to Count USPS Business Days for Delivery Estimates
A USPS business day delivery calculator counts Monday to Saturday, not federal days. Here is the one rate worth tracking and the point where you act on it.
Guides
Best subtract business days tools 2027: facts and context, explained properly
Six named tools that count backward from a deadline, what each one does with weekends and regional public holidays, and where the counting rules come from.
Guides
Days between dates holidays: past and future windows
How a closure changes a days between dates count, and why a window that has closed and one that has not must be counted against different lists.
Guides
Who actually publishes the state calendars that set a deadline?
Who publishes the state calendars that actually govern a deadline, why the personnel list is the trap, and how to build one office's calendar properly.
Guides
Working days per month formula: test vectors and checks for your code
Test a working days per month formula before you trust it: edge spans, a month-by-month 2027 sum, a day-by-day sweep and the off-by-one bugs.
Guides
Add Business Days: Four Assumptions to Set First
Before adding business days, identify the working week, closure authority, receipt cut-off and governing place, and record who can confirm each.