About

How the answers are made correct

• A business-day count is only as good as its holiday list, so Whendays offers one only where that list is sourced. Five countries are covered today: the United States, the United Kingdom, Germany, France, and Israel. The full inventory of certified jurisdictions, with the grain each calendar is true at and when each was last verified, is generated from the registry on the coverage page.
• A non-working day is two separate facts, the weekend and the public holidays, each traced to its own governing record. The public holidays come from the holiday authority itself: 5 U.S.C. §6103 for U.S. federal holidays, the Banking and Financial Dealings Act for UK bank holidays, Germany's federal and state holiday laws, France's Labour Code, and Israel's Law and Administration Ordinance with its Independence Day Law.
• The weekend comes from each country's rest-day rule where one exists: a statutory Sunday in the United States, Germany, and France, and a statutory Saturday (Shabbat) under Israel's weekly-rest law. The second weekend day is convention rather than statute: Saturday beside those Sundays, Friday beside Israel's Shabbat, and both of the United Kingdom's, which rest on convention alone.
• Where a country's holidays are not yet sourced, Whendays returns no business-day count rather than a guessed one. A missing answer is honest; a wrong deadline is not.
• The working week follows the country instead of an assumption: Israel's runs Sunday to Thursday, with Friday and Saturday as the weekend, and the count reflects that.
• Counting is by calendar date, not the clock. Whendays reads today's date in your detected time zone using the IANA Time Zone Database, so a "10 business days from today" answer holds even when your local date differs from the server's. Time zone changes how a date is displayed, never how many days are counted.
• Your country is inferred from your IP address to choose the right calendar, and IP location is approximate. If the detected country is wrong, the holidays will be too.

What the answers stand on

• Dates go in as ISO 8601 (YYYY-MM-DD) and come back formatted for your locale, so a number never means two things. Whendays stands on shared standards: ISO 8601 for dates, the IANA Time Zone Database for zones, and the national laws that define each country's holidays. It names them on purpose, because an answer is only as trustworthy as the record behind it.
• Each country is vouched only after its non-working days are corroborated against these sources, not taken on trust.

Data sources and attributions

Three bundled datasets carry their own attribution terms. They are credited here, in one place.

• The public-holiday dates, names, and types are compiled by the open-source date-holidays project and used, with light normalization, under a Creative Commons Attribution-ShareAlike 3.0 (CC BY-SA 3.0) license. The dataset is a convenience, not the authority: each vouched country's non-working days are corroborated against the governing records named above, and no business-day answer is returned for a country that has not been sourced.
• Location is inferred from your IP address to pick a default calendar. This site includes GeoLite2 data created by MaxMind, available from https://www.maxmind.com.
• Region and state names are shown using subdivision display names from Unicode CLDR (Unicode License V3), the same vocabulary the site's date and country formats already stand on.