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Holiday Data Methodology

How we source, scope, and update the holiday data behind every calculator on this site.

This site covers public holidays for 25 countries. Each country's national set is described below with the source it rests on. Two are banking calendars and say so: the financial-market business days of Brazil's Resolução CMN 4.880/2020 and the Bank of Israel's calendar of non-business days. A national set is not every day someone in the country has off: days that belong to one state, province, Land or canton are on the regional pages, and where a national set includes a day that part of the country does not keep, the country's line says so. The sections below cover what each set includes, how weekend dates are handled, and how dates that are not yet published are tagged.

What we cover by country

Each line names the set the country's data follows. Where a line rests on sources of its own, they are listed under it; every country's data source and its review date are listed under Sources and audit trail below.

What we exclude and why

For 7 countries the site keeps regional calendars on pages of their own, 88 jurisdictions in all, each built from the national set with that jurisdiction's own days added or removed; the sources register lists what each one rests on.

Concrete consequences: Civic Holiday is not in the Canada set, Patriots' Day is not in the US set, Reformationstag is not in the Germany set and the state Labour Days are not in the Australia set. Each calculator has an Advanced options section that takes custom dates and adds them to the country's list, so you can add the days that apply to you.

How we handle observed dates

Countries treat a holiday that falls on a weekend differently. Each line gives the rule its source states and what the data lists:

For a comparison of the weekend rules of the United States, the United Kingdom, Canada, Australia and continental Europe, see the guide on weekend observance.

How we handle lunar and Islamic dates

In several countries' data some holidays fall on a different Gregorian date each year, and the date for a later year is not published yet. Eight countries' data carries such dates today, computed and tagged as described below: China, Egypt, India, the Philippines, Qatar, Singapore, the United Arab Emirates and Vietnam.

Where the data holds the authority's published dates for a year, it uses them. Two sets carry computed dates with no tag: Israel's dates for 2028 and 2029 and Saudi Arabia's dates in every year. For a later year in the other countries the data carries a computed date and tags it (approximate) in the holiday list, because the published date can differ from it. For a deadline near such a holiday, check the date against the authority that publishes it, which each country's page names and the list under Sources and audit trail gives.

How we handle dates awaiting their annual order

A second kind of uncertainty has nothing to do with the calendar. India's Dr. Ambedkar Jayanti is on 14 April in every year of the data, but the one order read for this site covers a single year: an Office Memorandum of the Department of Personnel and Training dated 9 April 2026 (No. 12/4/2020-JCA), separate from the memorandum on the year's holidays, declared 14 April 2026 a holiday. The data carries the day in every year from 2024 to 2029; in 2028 it shares a row with Good Friday, and that row has no tag. In 2027 and 2029 the entry is tagged (unconfirmed). It says the calendar date is settled and the instrument confirming it is not, which is a different claim from the computed dates above and needs its own tag. Putting the lunar label on a fixed Gregorian date would be false, and leaving the entry bare would overstate what is known.

The same tag marks dates for Egypt, the Philippines and the United Arab Emirates that wait on an official act: in Egypt the decision that sets each later year's day off, in the Philippines the year's proclamation, in the United Arab Emirates the announcement of a holiday's day. Both tags clear the same way: once the authority publishes, the entry is replaced with what its instrument says.

Update cadence

Each country's data records the date it was last checked against its source; that date is shown on the country's pages and under Sources and audit trail below. Among the 25 countries the oldest of those dates is May 19, 2026 and the newest October 13, 2026. There is no fixed schedule for re-checking dates. An automated check runs every Monday and requests the cited source pages to see that they still answer; it does not re-read holiday dates. Not every date without an official list carries a tag: the country lines above say which years are this site's projections or conversions.

The holiday pages run from 2024 to 2028, and every calculator on the site reads the same data.

Sources and audit trail

Each country's holiday file names the official source it is checked against and records the date of the last check. The full set is below. A date tagged (approximate) is this site's computation and is on no authority's page yet.

Official source for each country

Structural drift, such as invalid dates, duplicates or holiday counts outside a band set for each country, is caught by the test suite. A check in the code base (npm run check:lunar-refresh) lists every entry tagged (approximate) or (unconfirmed) whose date is within six months, so the published date or the annual order can replace it. The check runs on demand, not on a schedule.

This page lists the official source for each of the 25 countries. The full register, with a link where the source has one and the last-reviewed date for all 113 jurisdictions (these 25 countries plus the 88 sub-national ones), is on the sources register.

What to do if you find an error

If you spot an incorrect date or a missing holiday, please get in touch. Include the country, the date and the source you are relying on, such as a government calendar or proclamation.

Each country's holidays are stored as data, one list per year, with the source URL and the review date. Every calculator and holiday table on this site reads the same file, so a corrected date reaches all of them at the next deploy, and a change to a holiday date is recorded on the updates page. Sentences that describe a country's set, like the lines on this page, are written by hand and are corrected with the data.

Sources for these rules

Checked October 13, 2026. All sources

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