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Business Days Calculator

Business days show working time, which is what most deadlines, shipping times and processing periods use. 22 business days fall in a 30-day span, with 8 weekend days. Use it to estimate delivery windows, payment terms, project durations and notice periods that are stated in business days.

Remember that a deadline of 10 business days is about two calendar weeks, not 10 calendar days.

Business Days Calculator: inputs

Calculated result
Business days22
Calendar days30
Weekend days8

Business Days Calculator: Start date sensitivity

Business Days Calculator: Start date and Business days5 calculations vary the “Start date” input while holding the other entered inputs constant.August 18, 202632August 25, 202627September 1, 202622September 8, 202617September 15, 202612

Enter the start date and end date. Check the endpoint convention before using a calendar total for a contractual deadline. Public holidays are not automatically inferred from the country or employer.

It does not know about public holidays, which differ by country and by employer, so subtract them yourself. For a due date some business days from now, work out the end date and adjust for holidays.

Business Days: worked example

Start dateSeptember 1, 2026
End dateSeptember 30, 2026
Business days22
Calendar days30
Weekend days8

Holidays are not deducted, so the true number of working days can be lower. Some businesses work Saturdays, and some countries have different weekends. Whether the start date counts depends on the rule: this tool includes both endpoints.

Time zones can shift the date at the boundaries.

Business Days: formula

Business days = weekdays (Monday to Friday) from the start date through the end date, both included

NIST: Official U.S. Time

Common error: Counting from the day after the start. A range that includes the start date has one more day than one that begins the next morning.

Business Days: changing Start date

Start dateBusiness daysCalendar daysWeekend days
August 18, 2026324412
August 25, 2026273710
September 1, 2026 (example)22308
September 8, 202617236
September 15, 202612164

Business Days: compare input ranges

InputTested fromToBusiness days: low inputBusiness days: high inputSwing
Start dateAugust 25, 2026September 8, 2026271710 (45%)
End dateSeptember 23, 2026October 7, 2026172710 (45%)

Business Days: individual input comparisons

InputValueBusiness daysCalendar daysWeekend days
Start dateAugust 18, 2026324412
August 25, 2026273710
September 1, 202622308
September 8, 202617236
September 15, 202612164
End dateSeptember 16, 202612164
September 23, 202617236
September 30, 202622308
October 7, 2026273710
October 14, 2026324412

Business Days: combined input changes

Start date / End dateSeptember 16, 2026September 30, 2026October 14, 2026
August 18, 2026223242
August 25, 2026172737
September 1, 2026122232
September 8, 202671727
September 15, 202621222

Business Days: which assumptions move the result?

Business Days: Business days as Start date changesBusiness days starts at 32. Moving Start date from August 18, 2026 to September 15, 2026 changes it to 12, with End date September 30, 2026 kept fixed.August 18, 202632August 25, 202627September 1, 202622September 8, 202617September 15, 202612
Chart quantityDisplayed settings
Start dateAugust 18, 2026 → September 15, 2026
Business days32 → 12
End dateSeptember 30, 2026
Business Days: Business days as End date changesBusiness days starts at 12. Moving End date from September 16, 2026 to October 14, 2026 changes it to 32, with Start date September 1, 2026 kept fixed.September 16, 202612September 23, 202617September 30, 202622October 7, 202627October 14, 202632
Chart quantityDisplayed settings
End dateSeptember 16, 2026 → October 14, 2026
Business days12 → 32
Start dateSeptember 1, 2026

Business Days: values and definitions

Quantity and definitionValue used
Start dateSeptember 1, 2026
End dateSeptember 30, 2026
Business days22
Calendar days30
Weekend days8

Date & Time calculators: Age Calculator, Date Difference and Countdown Calculator, Day of the Week Calculator, Add Days to a Date Calculator.

A 30-day span holds only 22 working days when it starts on a Tuesday, because eight fall on weekends. That gap is the difference between a promised turnaround and a real one. The page counts Monday through Friday with both end dates included, so it answers how many days someone could work, before any holiday is removed.

Subtract any public holidays that fall inside the range yourself. The count treats every weekday as a working day.

Count calendar days on the date difference calculator, add days on the add days to date page, and see the weekday on the day of the week calculator. The time card calculator handles hours within a day, and the day counter counts down. Check holiday calendars for your country.

What counts as a business day?

Normally Monday through Friday excluding public holidays. This calculator counts weekdays and does not remove holidays.

How many business days are in a year?

Count the selected calendar year, workweek and applicable holiday list. A fixed annual working-day estimate does not determine the dates for a particular employer or jurisdiction.

How do I include holidays?

Subtract the number of public holidays that fall on weekdays within the period from the result, using the calendar for your country or employer.