Japan Business Day Calculator with National Holidays
Work out business days in Japan, skipping weekends and national holidays. Find the due date that is N business days after (or before) a date, count the business days between two dates, or list the holidays of any year from 2000 to 2099. Substitute holidays and “citizens’ holidays” are included, and the holidays are computed from the rules of Japanese law, including the spring and autumn equinoxes. Everything runs in your browser, and nothing you type is sent to a server. To count plain calendar days, use the Date Calculator.
🔒 Runs in your browser · Your data is never sent to a server
Date N business days from a date
Use a positive number for the future and a negative one for the past (for example -5).The start date itself is not counted.
Business days in a date range
Holidays by year
How to use
- Under “Non-working days”, choose whether holidays and the year-end break count as days off.
- In “Date N business days from a date”, enter a start date and a number of business days to see the due date.
- In “Business days in a date range”, enter a start and end date to see business days, weekends, and holidays.
Notes
- Holidays are computed from the current Japanese holiday law for 2000–2099, including the 2020 and 2021 Tokyo Olympics shifts and the special holidays of the 2019 imperial transition.
- Future legal changes and one-off holidays are not reflected. For important deadlines, also check the Cabinet Office’s list of national holidays.
- Saturdays and Sundays are always treated as days off. Company-specific closures (founding anniversaries, Obon, etc.) are not included.
- The range count includes both the start and end dates. If the start is after the end, the two are swapped automatically.
Glossary
Substitute holiday (furikae kyujitsu)
When a national holiday falls on a Sunday, the next weekday that is not itself a holiday becomes a day off. For example, if May 3 is a Sunday, May 6 becomes the substitute holiday, skipping Greenery Day and Children’s Day.
Citizens’ holiday (kokumin no kyujitsu)
A weekday sandwiched between two national holidays becomes a day off. It appears in September in years when Respect for the Aged Day falls two days before the autumnal equinox.
Happy Monday system
Coming of Age Day, Marine Day, Respect for the Aged Day, and Sports Day fall on a set Monday of the month instead of a fixed date, creating three-day weekends.
FAQ
Is the start date counted when I add business days?
No. Counting begins the day after the start date, and only business days are counted. For example, one business day after a Friday is the following Monday (unless it is a holiday). If your contract counts the start date as day one, subtract one from the number of business days.
Are substitute holidays and citizens’ holidays included?
Yes. When a national holiday falls on a Sunday, the next weekday that is not a holiday becomes a substitute holiday (the rule since 2007), and a weekday between two holidays becomes a citizens’ holiday. Both are added automatically and labeled in the holiday list.
Which years are supported?
Years 2000 through 2099. The equinox dates are computed with an astronomical approximation that matches the official announcements in this range. Future law changes and one-off holidays are not reflected, so check the Cabinet Office list for critical deadlines.
Can I add company holidays like Obon or a founding day?
Only the year-end break (Dec 29 – Jan 3) can be toggled. Company-specific closures are not supported, so adjust the resulting date by hand for those days.
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