Business Days Calculator

Two questions, one calculator

Almost every business-day question is one of two shapes. Either you have two dates and need to know how many working days sit between them, which is what invoice terms, notice periods and service levels are counted in, or you have one date and a number of working days and need the date you land on. Both are here, on the two tabs above, sharing the same weekend and holiday settings so you never have to enter them twice.

The weekend is not the same everywhere

Saturday and Sunday is the common case, but it is far from universal. Much of the Gulf works a Friday and Saturday weekend or, since 2022 in the UAE, a Friday afternoon and full Saturday. Nepal has a one-day weekend on Saturday. Many Indian offices and most banks run a six-day week with only Sunday off, and plenty of factories run every day. Picking the wrong weekend silently changes the answer by twenty percent or more over a month, so it is a setting rather than an assumption.

Holidays are yours to list

There is no built-in holiday calendar here, and that is deliberate. A national list is wrong for anyone whose state adds its own days, wrong for a company with a shutdown week, and out of date the moment a government moves a date, which happens every year. A stale list that looks authoritative is worse than no list, because you would not think to check it. Paste your own dates instead, one per line, and add the name after the date if it helps you read them back. A date the calculator cannot read is reported rather than quietly ignored, since a typo that drops a holiday from the count leaves no trace in the answer.

Counting the end date, or not

This is the detail that makes two calculators disagree. "Five working days from Monday" usually means you finish on the following Monday, counting forward five days and not counting the start. "How many working days between the 1st and the 30th" usually means the days you will actually work, which includes both ends. The checkbox lets you say which you mean, and the summary line always spells out the choice that produced the number, so you can check it against whatever contract or policy you are working from.

Why the dates never drift

Dates here are handled as plain calendar dates rather than as moments in time. It is a small thing that matters: a naive loop that adds twenty-four hours at a time skips or repeats a day in every country that changes its clocks, because a day is 23 or 25 hours long twice a year. Nothing on this page has a clock time attached, so nothing can drift.