Business Days Calculator — Skip Weekends & Holidays

A business day (also called a working day) is any day that is not a Saturday, Sunday, or public holiday. This tool counts Monday through Friday as business days and excludes Saturdays and Sundays automatically. However, public holidays vary by country, region, and year — Japan has 16 national holidays per year, the United States has approximately 10 federal holidays, and the United Kingdom has 8–9 bank holidays. This tool does not automatically remove public holidays because doing so would require knowing the user's country and the specific year. To account for holidays, calculate the business days first, then subtract the number of public holidays falling within the period. For Japan, the standard holidays include New Year (January 1–3 effectively), Coming of Age Day, National Foundation Day, Vernal Equinox Day, Showa Day, Constitution Day, Greenery Day, Children's Day, Marine Day, Mountain Day, Respect for the Aged Day, Autumnal Equinox Day, Sports Day, Culture Day, Labour Thanksgiving Day, and Emperor's Birthday.

Service Level Agreements (SLAs) and contracts often specify timeframes in business days rather than calendar days. For example, a "5 business day" response commitment starting on a Wednesday means the deadline is the following Wednesday (5 business days = Wed, Thu, Fri, Mon, Tue — so due the next Wednesday). This tool calculates the count between two dates, but for deadline calculation you need to find the date that is N business days after a start date. For that, use the Date Add/Subtract Calculator on this site — set the unit to business days. In legal contracts, "business day" definitions sometimes explicitly include or exclude the start date; always check the contract language. Japanese commercial law and standard purchase orders often define "営業日" (business days) as days when banks are open, which excludes year-end and New Year holidays (roughly December 31 through January 3).

When planning project timelines, business day calculations help estimate realistic durations. A two-week sprint in agile development contains 10 business days, assuming no holidays. A month-long project (April 1 to April 30) contains approximately 22 business days (minus any holidays). To plan a project correctly, use this tool to count business days between milestone dates, then verify the count is realistic given your team's capacity. When a project spans a period with multiple public holidays (such as Japan's Golden Week in late April and early May, which clusters Constitution Day, Greenery Day, and Children's Day), remember to subtract those days. The business days count plus a manual holiday subtraction gives you the true working days available.

Business payment terms are typically expressed in business days: "Net 30" means payment is due 30 calendar days after the invoice date (not business days, despite common confusion). "30 business days" would be significantly longer — about 6 calendar weeks. Japanese invoicing practices often use month-end cutoffs: invoices received by the 20th of the month may be payable by the end of the following month (月末締め翌月払い). When calculating due dates, enter the invoice date as the start and count forward to the cutoff date. For international transactions, be aware that banking holidays in the counterparty's country can delay settlement even if the sending bank processes the payment — use this tool to verify the business day count and plan settlements accordingly.

Whether to include the end date depends on your counting convention. In most project planning and SLA contexts, the end date represents the deadline and should be included in the count — so "5 business days from Monday" counts Monday, Tuesday, Wednesday, Thursday, and Friday as 1–5, meaning the deadline is Friday. In some financial contexts, the count is exclusive of both start and end dates — this is common in bond interest accrual calculations. Toggle the "Include end date" option to match your specific use case. When in doubt, include the end date and verify the result against a known example: "How many business days are between Monday and Friday of the same week?" — with end date included, the answer is 5 (Mon, Tue, Wed, Thu, Fri).