Working Days Calculator
Contracts, notice periods and delivery estimates are almost always counted in working days, which is a different number from calendar days.
What counts as a working day
This calculator defines a working day as Monday to Friday. That covers most of the world, but the assumption is not universal:
- Friday–Saturday weekends apply in Afghanistan, Iran and some Gulf states, though many have moved to Saturday–Sunday for business.
- Six-day weeks remain common in parts of Asia and in some sectors.
- Half-days and shift patterns fit no simple rule.
Public holidays are not built in, because they differ by country, by region and by year — and even within one country, as England, Scotland and Northern Ireland demonstrate. Enter the number that falls in your period and the calculator deducts it.
How the counting works
When counting between two dates, the calculation walks the calendar day by day and counts each weekday, excluding the end date. This matches the usual convention where a deadline of “10 working days” from Monday means the following Monday.
When adding working days, the calculation steps forward one day at a time, skipping Saturdays and Sundays, until the required number of working days has elapsed. Adding 5 working days to a Monday lands on the following Monday; adding 1 working day to a Friday lands on the Monday.
A rough sanity check: working days ≈ calendar days × 5/7. Twenty working days is approximately 28 calendar days, or four weeks.
Working days in contracts and law
Deadlines expressed in working days appear constantly, and the definitions vary:
| Context | Typical convention |
|---|---|
| UK consumer returns | 14 calendar days to cancel, 14 more to return |
| Bank transfers (SEPA) | 1 business day, excluding TARGET holidays |
| Employment notice | Usually calendar weeks, not working days |
| Court filing deadlines | Clear days, often excluding both ends and holidays |
| Commercial delivery | Working days, supplier's own holiday calendar |
Where a deadline matters, read the exact wording. “Within 10 working days”, “10 clear working days” and “by the 10th working day” can produce three different dates.
Frequently asked questions
Does this include public holidays?
Not automatically — there is no universal holiday calendar. Enter the number of public holidays falling within your date range and they are deducted from the total.
How many working days are there in a year?
Around 261 weekdays in a typical year, or 262 in some. Subtract your country's public holidays — usually 8 to 14 — for roughly 250 actual working days.
What if my week is not Monday to Friday?
The calculator assumes a Saturday and Sunday weekend. For a different pattern, use the calendar days figure from the date difference calculator and apply your own fraction.