How business days are counted
This calculator uses the standard commercial convention: the start date is not counted, the end date is. That matches how deadlines are stated in practice. If a supplier promises delivery in 3 business days and ships on Monday, the three days are Tuesday, Wednesday, and Thursday; the day the clock starts is not one of them. Payroll cut-offs, court filing deadlines, and bank settlement periods follow the same pattern. If your contract counts both endpoints, simply add one working day to the result.
Saturday and Sunday are treated as non-working days, which is the most common weekend worldwide but not universal: some countries in the Middle East and North Africa rest on Friday and Saturday. Public holidays are even less predictable, varying by country, region, and year, so instead of guessing them the tool asks you for a count. Look up the holidays that fall on a weekday within your range, enter how many there are, and they are deducted from the business day total.
Frequently asked questions
Why isn't the start date counted?
Because that is how business deadlines usually work: "in 3 business days" from Monday means Tuesday, Wednesday, Thursday. The day the clock starts is day zero. If your situation counts both endpoints, add one working day to the result.
What about countries with a Friday-Saturday weekend?
The tool assumes Saturday and Sunday off. Both weekend patterns remove two days per week, so totals are usually similar, but the edges of the range can differ by a day or two. Count those boundary differences yourself and add them to the holidays field.
How do I handle half days?
The calculator works in whole days only. Either ignore half-day closures, count each one as a full holiday for a conservative estimate, or pair two half days together and enter them as one holiday.