Practical guides
Original explanations, clear examples and the assumptions that change your answer.
Business days versus calendar days: count a real timeline
See how weekends, holidays and endpoint choices change a business-day count, with a worked November example.
Read the guide ↗Guide 02 / Worked examplesAdd or subtract business days without an off-by-one error
Understand day zero, weekend starts, zero-day offsets and backward scheduling through a worked five-day example.
Read the guide ↗Guide 03 / Worked examplesObserved federal holidays and the December 31 edge case
Understand observed dates, cross-year New Year holidays and the limits of a recurring US federal holiday preset.
Read the guide ↗Guide 04 / Worked examplesCustom weekends and company closures: build the calendar you use
Plan a Sunday–Thursday week or a company shutdown without double-counting dates or assuming federal employee rules.
Read the guide ↗Guide 05 / Worked examplesWhy daylight saving and leap years should not confuse a workday count
See why a date-only calculator counts civil dates instead of dividing hours by 24, with leap-day and DST examples.
Read the guide ↗Guide 06 / Worked examplesPlan a project handoff with a transparent working-day schedule
Build a two-stage project timeline, show the counted dates and separate processing time from an explicit buffer.
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