World Calendar 1900–2100
National, international, and religious holidays for any year from 1900 to 2100 — Christian, Islamic, Hindu, Sikh, Jewish and more.
September 2026
4 holidays this month
Holidays in September 2026
Krishna Janmashtami
Friday · Hindu · static
Ganesh Chaturthi
Tuesday · Hindu · static
Urs of Shaykh Abdul Qadir Jilāni ق
Tuesday · Islamic · Aladhan
Urs of Imām Abu Hamīd al-Ghazzāli ق
Friday · Islamic · Aladhan
A perpetual, multi-tradition calendar
This calendar spans two centuries (1900 to 2100) and combines multiple data sources so you can plan family, business, and spiritual events across traditions:
- National holidays from the open Nager.Date dataset for 100+ countries.
- Christian moveable feasts (Easter, Good Friday, Ascension, Pentecost) computed locally using the Meeus/Jones/Butcher Computus algorithm — accurate for every Gregorian year.
- Islamic holidays from the free Aladhan Hijri calendar API (Eid al-Fitr, Eid al-Adha, Mawlid, Islamic New Year, Ramadan start).
- Hindu, Sikh, Jewish, Buddhist holidays from a curated dataset, with the Calendarific slot ready to plug in a paid key for full 200-year coverage.
When you're offline or a live API is rate-limited, the calendar transparently falls back to a bundled JSON dataset so you always see at least the major festivals.
How the World Calendar Works
This tool displays multiple calendar systems side by side for any given date. When you pick a date, the tool reads it as a Gregorian date and then converts it into other systems such as Hijri (Islamic), Vikram Samvat, Shaka Samvat, and the Chinese lunar calendar. Each conversion relies on that calendar's own mathematical rules — lunar calendars are calculated from the moon's orbital cycle, while solar calendars are based on Earth's revolution around the sun.
The tool also maintains a database of national and religious holidays, kept separately for each country so dates and festivals stay accurate. Leap year rules differ across systems — the Gregorian calendar adds a leap day roughly every four years, while the Islamic calendar, being purely lunar, runs about 11 days shorter than a solar year. The tool automatically accounts for this drift when converting between systems.
It's especially useful for people coordinating with international teams, planning around festivals or holidays across countries, or doing historical and cultural research that requires comparing dates across calendar systems. All conversion happens directly in the browser, so no data is sent to a server and results appear instantly.