What is a business day?
A business day is a calendar date that is treated as a working day under the schedule you choose. A common Monday-to-Friday workweek excludes Saturday and Sunday, but working weeks can differ by organization and location. This calculator therefore lets you choose which weekdays should be excluded.
How to calculate business days between two dates
Choose the start date and end date, then confirm which weekdays are non-working. The calculator checks each date in the selected period and removes excluded weekdays and any custom holiday dates you enter.
The result also shows how many calendar dates were considered, how many non-working weekdays were removed and how many entered holidays reduced the working-day total.
Including or excluding the start and end date
Both endpoints are included by default. You can turn off Include start date or Include end date when your calculation should begin after the first date or stop before the final date.
If a custom holiday falls on a weekday that is already marked as non-working, it is not deducted a second time. This prevents the same date from being counted in two exclusion categories.
Add or subtract business days
Switch the calculation mode when you know a starting date and a number of working days instead of two endpoints. Choose whether to add or subtract the interval and the calculator will skip your selected non-working weekdays and custom holidays.
The starting date itself is not counted as business day number one in this mode. For example, adding one business day to a Monday moves to Tuesday when Tuesday is an ordinary working day.
Business days example
Suppose a period runs from Monday through the following Friday and both endpoints are included. With Saturday and Sunday excluded and no custom holidays, the calculator counts the five weekdays in the first workweek and the five weekdays in the second workweek.
If one of those weekdays is entered as a holiday, the business-day total decreases by one. If the holiday falls on a Saturday or Sunday that is already excluded, the result does not decrease again.
Business days vs. calendar days
Calendar-day calculations include every date regardless of weekday. Business-day calculations apply working-day rules instead. Use the Days Between Dates Calculator for a pure calendar-day interval, or the Date Calculator to add or subtract ordinary calendar days.
Business days vs. work hours
A business-day count does not determine how many hours were worked on each date. If you need to calculate the duration of a shift, use the Work Hours Calculator. For weekly clock-in and clock-out records, use the Time Card Calculator.
Frequently asked questions
Does the calculator exclude weekends?
Yes. Saturday and Sunday are selected as non-working days by default, and you can change the excluded weekdays when your workweek is different.
Does it know public holidays automatically?
No. Public holidays depend on the relevant country, organization and calendar. Enter the holiday dates that should apply to your specific calculation.
Can I count Friday and Saturday as my weekend?
Yes. Select Friday and Saturday as non-working weekdays and clear any weekdays that should remain part of your workweek.
Can I calculate a deadline 20 business days from a date?
Yes. Switch to the add or subtract mode, enter the start date and 20 business days, then apply your weekend and holiday settings.
What if I enter the two dates in reverse order?
The calculator still counts the selected period and identifies that the dates were entered in reverse order. You can also use the Swap dates button.
Using this calculator effectively
The Business Days Calculator counts working dates between two endpoints or finds a date a chosen number of business days forward or backward. Weekend rules and custom holiday dates can be adjusted for the schedule being used.
Common uses
- Counting working days between two project, delivery or administrative dates.
- Finding a deadline a set number of business days before or after a starting date.
- Adjusting a working-day calculation for a custom weekend or known holiday dates.
Tips for a better estimate
- Confirm which weekdays are treated as non-working for the schedule that applies to you.
- Add the relevant holiday dates instead of assuming every location follows the same holiday calendar.
- Check whether the start date and end date should be included in the count before using the result.
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