Where do the holidays come from?

The Cabinet Office's official rules for Japanese national holidays, implemented in JavaScript. Fixed-date holidays, Happy Monday rules, vernal/autumnal equinoxes via astronomical formula, plus substitute and citizen's holidays. Coverage: 1955–2099.

What is the 'Treat Saturday as a business day' option for?

Some industries (construction, retail, healthcare) routinely operate on Saturdays. Turn this on when 'N business days' for your domain includes Saturday. Default is OFF (Saturday is a non-business day).

Are the Tokyo 2020 Olympics holiday moves handled?

Yes. Marine Day, Sports Day, and Mountain Day were specifically moved for the Tokyo Olympics in 2020 (Jul 23 / Jul 24 / Aug 10) and 2021 (Jul 22 / Jul 23 / Aug 8). Both years are reflected.

Does the calculator include 'citizen's holidays' during Golden Week?

Yes. May 4 was historically (1988–2006) a 'citizen's holiday' sandwiched between Constitution Memorial Day (May 3) and Children's Day (May 5). From 2007 onward May 4 became Greenery Day, removing the citizen-holiday status. The tool reflects this history.

Is the start date counted as a business day?

No. The start date is a reference point. 'N business days after' returns the Nth business day starting from the day after the start date; 'N business days before' counts backward similarly. This matches the standard interpretation used in Japanese business contracts.

Is any date information uploaded?

No. All math runs in your browser; no dates or due-date data leave your device.

Back to Time

JP business-day calculator — count workdays excluding holidays

Compute the date that is N business days before or after a given date, skipping Japanese national holidays plus weekends. Handles substitute holidays, citizen's holidays, and vernal/autumnal equinoxes (1955-2099). Useful for due dates, settlement dates, and Japan-side delivery scheduling. Runs entirely in your browser.

timejapanesecalculator

How to use

Pick a direction (N business days after / before), set the start date and N, then press Calculate. The tool returns the result date with its weekday and the total calendar days elapsed. Enable 'Treat Saturday as a business day' for industries (construction, retail, healthcare) that operate on Saturdays. The default skips Saturday, Sunday, all Japanese national holidays, plus substitute and citizen's holidays.

FAQ

Where do the holidays come from?: The Cabinet Office's official rules for Japanese national holidays, implemented in JavaScript. Fixed-date holidays, Happy Monday rules, vernal/autumnal equinoxes via astronomical formula, plus substitute and citizen's holidays. Coverage: 1955–2099.
What is the 'Treat Saturday as a business day' option for?: Some industries (construction, retail, healthcare) routinely operate on Saturdays. Turn this on when 'N business days' for your domain includes Saturday. Default is OFF (Saturday is a non-business day).
Are the Tokyo 2020 Olympics holiday moves handled?: Yes. Marine Day, Sports Day, and Mountain Day were specifically moved for the Tokyo Olympics in 2020 (Jul 23 / Jul 24 / Aug 10) and 2021 (Jul 22 / Jul 23 / Aug 8). Both years are reflected.
Does the calculator include 'citizen's holidays' during Golden Week?: Yes. May 4 was historically (1988–2006) a 'citizen's holiday' sandwiched between Constitution Memorial Day (May 3) and Children's Day (May 5). From 2007 onward May 4 became Greenery Day, removing the citizen-holiday status. The tool reflects this history.
Is the start date counted as a business day?: No. The start date is a reference point. 'N business days after' returns the Nth business day starting from the day after the start date; 'N business days before' counts backward similarly. This matches the standard interpretation used in Japanese business contracts.
Is any date information uploaded?: No. All math runs in your browser; no dates or due-date data leave your device.

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