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Business Days Calculator

Counts the working days between two dates after removing the weekly weekend and any public holidays you enter.

Enter your numbers

Start date

Example: 2026-01-01

End date

Example: 2026-01-31

Public holidays in the period

Example: 2

Count Saturday as a weekend

Result

Currency

Figures are computed on your device; nothing is sent anywhere.

Formula

totalDays = endDate - startDate + 1; weekendDays = number of Fridays (+ Saturdays if includeSaturday); businessDays = totalDays - weekendDays - holidayCount

How the calculation works

Enter the start and end date of the period, and the tool counts the calendar days including both the first and the last date.

Enter how many public holidays fall in the period and choose whether Saturday is counted as a weekend day alongside Friday.

The tool subtracts the weekend days and the holidays you entered from the total days to give the number of business days.

Common mistakes

Forgetting to subtract holidays, which inflates the working days and makes a deadline look easier than it really is.
Treating Saturday as a working day when your office or the contract closes on Saturday, which adds four or five extra days a month.

When to use it

Use it to set a realistic deadline for a project, since a month is not thirty working days once weekends and holidays are removed.
Use it to work out payment or delivery terms, where a contract counts working days rather than calendar days.

Worked example

From 1 January to 31 January 2026 there are 31 days, and with 5 Fridays, 2 public holidays and Saturday not counted, the business days come to 24.

Total days 31

Weekend days 5

Business days 24

Common questions

Are both the start and end dates counted?

Yes, the tool includes both the first and the last date, so a period from the first to the tenth of a month is counted as ten calendar days.

Last updated: 2026-10-03