What is a business day?
In this calculator, a business day is a date whose weekday is selected as working and is not in your excluded-date list. Monday through Friday is the default, not a universal rule.
Time & Date · Working calendar
Business Days Calculator
Count business days between dates or add and subtract working days. Use a Monday-Friday default or define your own working weekdays and excluded dates.
Ready to calculate
Business days vs calendar days
Calendar days include every date. Business days apply your working-week and exclusion rules. See the Business Days vs. Calendar Days guide.
Endpoint inclusion
Count mode includes both Start and End by default. Monday through Friday therefore counts as five business days when all five weekdays are working and none is excluded.
Adding business days
The Base date is day zero. From a Friday, adding one business day normally lands on Monday under the default Monday-Friday workweek.
Custom workweeks
Choose any one to seven working weekdays. This supports schedules such as Sunday-Thursday, Monday-Saturday, or four-day workweeks.
Excluded dates
Add public holidays, company closures, or personal schedule exceptions yourself. An excluded date that already falls on a non-working weekday does not reduce the count twice.
Leap years and dates
The app uses deterministic proleptic Gregorian date arithmetic from year 0001 through 9999. It does not use time zones, daylight-saving time, or time of day.
Different from Date Calculator
Date Calculator handles general calendar-date differences and shifts. Business Days Calculator filters dates through your working calendar.
Different from work-hours calculators
This app counts dates, not hours worked. Use Hours Calculator or Time Card Calculator when the task is about clock time, shifts, lunches, or weekly punches.
Consequential deadlines
This app does not determine authoritative legal, tax, banking, shipping, trading, or contractual deadlines. Verify the applicable calendar and rules for consequential dates.
