Working Days Calculator | Calculate Business Days Fast

What is a working days calculator?

A working days calculator counts the number of weekdays between two dates. It counts Monday through Friday and skips Saturday and Sunday. It does not remove public holidays, so the result is a count of weekdays, not a count of days the office happens to be open.

How to use the calculator

1. Enter a start date.
2. Enter an end date.
3. The result updates by itself. There is no separate "Calculate" button.
4. Select "Reset" to return both fields to the sample dates.

Both dates are included in the count if they fall on a weekday. For example, a range that starts on a Monday and ends on the following Friday counts both the Monday and the Friday.

Working days formula

The calculator checks every calendar day in the range, one by one, and keeps a running count of the days that are not a Saturday or a Sunday. This is the same as the shorter formula:

1Working days = Total calendar days in the range − Weekend days in the range
2

"Total calendar days" is the count of every day from the start date to the end date, including both endpoints. "Weekend days" is the number of Saturdays and Sundays in that same span.

Example

The calculator loads with a default sample: a start date of Monday, January 8, 2024, and an end date of Friday, January 12, 2024. That range covers five calendar days, all of them weekdays, so the result is 5 working days.

A second example shows how a weekend is handled. From Friday, January 12, 2024, to Monday, January 15, 2024, the range covers four calendar days: Friday, Saturday, Sunday, and Monday. Saturday and Sunday are skipped, so the result is 2 working days.

Edge cases

Start date after end date. If the start date is later than the end date, the calculator returns 0. It does not show an error message and does not return a negative number. The page also displays a short note confirming the result is 0.

Start or end date on a weekend. A weekend date at either end of the range is simply not counted. The days between it and the other endpoint are still counted normally.

Same start and end date. If both fields hold the same date, the result is 1 when that date is a weekday, and 0 when it is a Saturday or Sunday.

Long ranges and leap years. Because the calculator checks every day individually, it stays accurate across any length of range, including spans of several years and ranges that cross a leap year.

Public holidays. The calculator does not know about holidays. A national holiday that falls on a Tuesday is still counted as a working day.

Working days versus business days

The terms are often used to mean the same thing, but some organizations draw a line between them: "working days" as any Monday through Friday, and "business days" as a Monday through Friday that is not a public holiday. This calculator follows the first, simpler definition. Excluding holidays would require a list of holiday dates for a specific country or region, which this tool does not use.

Some regions run on a different week entirely. Several countries in the Middle East treat Sunday through Thursday as the work week and Friday and Saturday as the weekend. This calculator always uses the Monday-to-Friday week and cannot be switched to a different pattern.

Common uses

People use working-day counts to plan project deadlines, calculate contract or notice periods, estimate delivery times, and work out payroll periods. A shipping company might promise delivery "within 5 working days," which excludes the two weekend days from the promise. A contract that gives someone "10 working days" to respond effectively grants two calendar weeks.

Frequently asked questions

What counts as a working day?

Monday, Tuesday, Wednesday, Thursday, and Friday. Saturday and Sunday do not count.

Does the calculator exclude public holidays?

No. It only excludes weekends. A holiday that falls on a weekday is still included in the count.

What happens if the start date is after the end date?

The calculator returns 0. It does not produce an error or a negative number.

What happens if a chosen date falls on a weekend?

That specific date is not counted, but the calculator still counts the weekdays elsewhere in the range as usual.

How many working days are in an average month?

A month with 30 or 31 days usually has 20 to 23 working days, depending on how the weekends line up. February usually has close to 20.

Is a working day the same as a business day?

Often yes, but some definitions of "business day" also exclude public holidays, while "working day" here means only Monday through Friday.

References

1. International Labour Organization, "Working Time." https://www.ilo.org/global/statistics-and-databases/statistics-overview-and-topics/working-time/lang--en/index.htm
2. Wikipedia, "Workweek and weekend." https://en.wikipedia.org/wiki/Workweek_and_weekend