Business Days Calculator (Japan)
Add N business days from a start date, or count business days in a range. Excludes weekends and Japanese national holidays. Everything stays in your browser.
How to Use the Japan Business Days Calculator
Use this calculator when you need a deadline, delivery estimate or workday count based on the Japanese calendar. Choose Add N days to move forward by a number of business days, or choose Count in range to count the working days between two dates.
Weekends and Japanese national holidays are skipped. The result also shows which holidays were found in the selected range when holiday data is available.
Worked Examples
- Add 10 business days: choose a start date, enter
10, and the result shows the Japanese business-day deadline. - Count January 2025: choose Count in range, set January 1 to January 31, and the calculator excludes weekends plus New Year and Coming of Age Day.
Japanese Holiday Rules Used Here
This tool is for Japan-style business day calculation. It excludes Saturdays, Sundays, Japanese national holidays, substitute holidays and the built-in citizens' holiday entries included in the local holiday table. Company-specific holidays, bank holidays outside the national holiday table and year-end office closures are not added automatically.
The built-in table covers 2024 through 2027 and is checked against the Cabinet Officeโs official National Holidays list (last checked July 14, 2026). A warning appears when the requested range extends outside those years.
How the Start Date Is Counted
The start date is excluded by default. If it is Monday, January 6, 2025, then January 7 is day one and the tenth business day is Tuesday, January 21, after skipping the January 13 holiday and weekends. Enable โInclude start dateโ and the same calculation returns Monday, January 20. A start date that falls on a weekend or holiday is never counted.
Good For
- Estimating Japanese shipping, support or review deadlines.
- Checking workdays for clients, vendors or teams in Japan.
- Counting Japanese business days without sending schedule data to an online service.
For a year-by-year calendar, use Japanese Public Holidays. For ordinary date differences or additions that should not exclude holidays, use the Date Calculator.