Costs
Country calendars mistakes, and the fixes that hold
Nine country calendars mistakes: assuming a Saturday and Sunday weekend, copying resolved dates for a rule-based closure, and treating a country as a timezone.
Desk
Review Desk
Side-by-side work on workday date calculator, held to the same conditions each time.
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.
Rules
Spreadsheet Date and Workday Counting Mistakes
Spreadsheet date and workday-count mistakes: text dates, locale-dependent imports, midnight shifts, serial values, endpoint rules, and closure ranges.
Rules
Federal Holiday Business Day Counting: Project Dates
Federal holiday business day counting with a real 2025 Memorial Day example, the one-day date shift, and a formula for rebuilding the schedule.
Industry
Before you act on SLA deadline calculators formula
The SLA deadline calculators formula: walk the schedule to find a due moment, keep a segment ledger for pauses, and handle the two boundaries that break both.
Features
Building state calendars in Excel with one column per layer
State calendars in Excel: one column per layer, a union built with a formula rather than by hand, and the lookup that picks the right layers for a row.
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.
Reviews
Six inputs a workday calculator needs before it can answer
Six inputs a workday calculator needs first, what each missing closure layer or default does to the answer, and how to check the skipped days by hand.
Maintenance
Country calendars holidays: a review routine for each new national closure list
A step-by-step routine for reviewing a new national closure list against the old one, so country calendars holidays changes never move a count unseen.
Industry
What separates the strong country calendars examples from the weak
Country calendars examples compared by name, from Canada and the United States to Saudi Arabia, showing where each one quietly moves a deadline.
Rules
Alberta Energy Regulator filings, counting business days in Calgary and Edmonton
AER filing business days Alberta: how the regulator counts submission deadlines against Alberta statutory holidays, with worked examples for Calgary and Edmonton.
Rules
CRA business day deadlines: GST/HST and corporate dates
CRA business day deadlines for GST/HST and corporate returns: find the statutory date, check CRA holidays, and apply the weekend or holiday shift.
Guides
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.
Rules
Quebec Construction Holiday Business Days: Schedule Impact
Quebec construction holiday business days can distort project schedules because standard holiday lists omit the closure. Learn the date rule and adjust counts.
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.
Features
Working hours Google Sheets: setup and timezone trap
Set up working hours Google Sheets formulas with Open and Close ranges, holiday dates, elapsed-time formatting, and the spreadsheet and Apps Script time zones.
Industry
Two ways to total working days in a year using Excel formulas
Working days per year in Excel: a single NETWORKDAYS call, the SUMPRODUCT alternative that shows its work, and the checks that catch a wrong answer.
Features
What matters most in working days per month holidays
Working days per month in 2027: how a monthly closure list is sourced, versioned and applied, and why this page states no holiday date for any country.
Rules
Add business days: three start conventions and fifteen worked cases excluding the start
Fifteen worked add business days cases excluding the start, plus how the three start-day conventions and a closure really move an actual deadline.
Industry
How closures change an add-business-days count in 2027
Add business days in 2027: what a closed day costs a count, the four ways two closure lists honestly disagree, and how to make an answer reproducible.
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.
Rules
Country calendars: three origins of a closed day
Country calendars: the three kinds of closed day, how a national list is published, and the fields to capture before you rely on one for a deadline.
Maintenance
Days between dates API: signal versus noise
Designing a days between dates API: plain dates against moments, the request and response fields worth echoing, and vectors that catch a merged type.
Rules
Days between dates formula: build the day number and test it
A days between dates formula built on a March-first day number, tested on leap days and century years, then reconciled with a spreadsheet's NETWORKDAYS.
Features
How SLA deadline calculators determine due dates
SLA deadline calculators turn contract rules into due moments; see how business-hour calendars, pauses, time zones, and boundary rules change the result.
Reviews
Spreadsheet or API: where the calendar should actually live
Spreadsheet or service: where the calendar lives, the contract a date must satisfy crossing between them, and one test set both sides should pass alike.
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.
Maintenance
Why a year's working day total starts with 260, 261 or 262 weekdays
Explains why a year's working day total starts with 260, 261 or 262 weekdays, how leftover days decide the count, and why closures and payroll divisors sit on top.
Industry
How to count working hours between two timestamps
Count working hours between two timestamps by clipping each day's window to the interval, with seven worked intervals and the same count in a spreadsheet.
Costs
Workday counts for a month: why length and starting weekday decide the total
Working days per month is 20 to 23 weekdays, decided by month length and start weekday: the rule behind it, a worked year, and where the count misleads.
Reviews
Days between dates: six honest answers to one simple-looking pair
One pair of days between dates, six honest answers: the unit, the endpoints, the calendar and the place that decide which number you were actually asked for.
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.