Plain DatesClear date calculations, with the rules shown.

Weekday calculator

Count or add business days

Count Monday-through-Friday dates in a range, or move forward and backward by business days. Add your own holiday dates when they apply to your schedule.

Business-day calculation

Enter ISO dates (YYYY-MM-DD), separated by commas, spaces, or new lines. Holidays are not added automatically.

What counts as a business day here?

A business day is any Monday, Tuesday, Wednesday, Thursday, or Friday that is not in your custom holiday list. This neutral definition is useful when you know which dates your organization observes, but it does not claim to provide an official holiday calendar for any country.

For counting ranges, the start date is eligible to count. The end date is excluded unless you select “Include the end date.” Reversed dates are accepted and reported as an earlier-to-later comparison.

Custom holiday example

For a workplace closed on 2026-12-25, add that ISO date to the custom holiday box. If it falls on a weekday within the selected range, one business day is removed. Duplicate entries are ignored.

Limits

  • Custom holiday dates must use the unambiguous YYYY-MM-DD format.
  • The supported date range is 1900-01-01 through 2200-12-31.
  • Observed holidays, emergency closures, regional rules, and industry-specific calendars must be entered by the user.
  • Legal and financial deadlines may follow specialized counting rules; confirm those rules with the responsible authority.
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