Enter values and select Calculate.
Calculated result
How to use this calculator
- Choose Count between dates or Add/subtract business days.
- Keep Monday through Friday or select the weekdays for your schedule.
- Enter up to 100 excluded ISO dates for holidays, shutdowns, or days off.
- Review the explicit endpoint or start-day policy shown with the result.
Formula and method
A business day is a selected working weekday that is not in the custom exclusion set. Count mode uses explicit endpoint choices; add/subtract mode treats the start as day zero.
Worked example
With Monday through Friday selected, Friday plus one business day is Monday. A custom excluded Monday moves that result to Tuesday.
Assumptions and limits
- Public holidays are not excluded automatically.
- Default working days are Monday through Friday.
- Count mode excludes the start and includes the end by default.
- Add/subtract mode treats the starting date as day zero.
Understanding the result
The result follows the stated calendar or civil-clock rules rather than guessing a timezone, work policy, holiday calendar, or legal definition. Read the displayed endpoint and start-day policy before using a count in planning or records.
Common mistakes
- Assuming every country or employer uses the same holidays
- Subtracting an excluded date twice when it is already a weekend
- Leaving endpoint inclusion unstated
- Calling a custom schedule an official business calendar
Methodology note
The calculator uses strict ISO-style date components, Gregorian leap-year rules, explicit clock values, and the deterministic policy shown on this page. It does not call a remote calculation, timezone, geolocation, payroll, calendar, or holiday service.
This browser-local utility is a calculation aid, not legal, payroll, scheduling, employment, tax, or official-calendar advice. Confirm the rules that apply to your situation.