Date Today is a public-service almanac for the world’s calendar systems. We track today’s date in twenty-five distinct calendars — Islamic (Hijri), Hebrew, Persian, Chinese, Hindu, Tamil, Nepali, Bengali, Ethiopian, Coptic, Buddhist, Bahá’í, Julian, Gregorian, Mayan, Japanese, Korean, Burmese, Zoroastrian, ISO 8601, and their synonyms — plus over seven hundred date-arithmetic calculators for everyday questions like “what date is 72 hours from now?” and “what was 6 weeks ago?”
Why we exist
For most of human history, calendars were how civilizations told themselves who they were. They encoded religious cosmology, agricultural rhythm, dynastic memory, and astronomical observation. Today, in a world running on a single global standard (the Gregorian calendar), it is easy to forget that humanity still keeps time in many simultaneous ways — that today is also 1 Dhu al-Hijjah 1447 for two billion Muslims, 3 Sivan 5786 for fifteen million Jews, 1395 AY for the Zoroastrian community, and 13.0.13.10.17 in the Maya Long Count. We exist to make those parallel timelines visible, accessible, and accurate — for students, researchers, the religiously observant, travelers, diaspora communities, calendar enthusiasts, and anyone who has wondered what day it is somewhere else.
How our calendar conversions work
Every page on this site recalculates from your current moment on every page load. The hero card you see at the top of each calendar page is not a static value — it is computed in PHP from the system clock, using authoritative astronomical algorithms (Reingold & Dershowitz’s Calendrical Calculations, Meeus’s Astronomical Algorithms, the Umm al-Qura tabular algorithm for Hijri, the standard Jalali algorithm for Persian, and PHP’s built-in calendar extension for Hebrew and Julian conversions). We verify each algorithm against authoritative reference dates and re-test on every release.
About the author
Imran Khan studied comparative religion at SOAS, University of London, and has been writing about calendar systems and timekeeping for fifteen years. He maintains the calendar-conversion library that powers Date Today and verifies each entry against authoritative astronomical and ecclesiastical sources. The library is open about its provenance: for Islamic dates, the Umm al-Qura tabular algorithm with a noted ±1-day local-sighting variance; for Hebrew dates, PHP’s jdtojewish() built on Reingold’s algorithms; for Persian, the standard Jalali algorithm by Mohammad Khazaee; for Mayan, the GMT correlation constant (584283); for Ethiopian and Coptic, the classical Annianus/Diocletian epochs. Where a calendar admits more than one variant in current use (Zoroastrian Shahanshahi vs Kadmi vs Fasli; Thai BE vs Sri Lankan BE), we name which we display and why.
Sources and methodology
For cultural and religious context — the significance of each month, the major festivals, the historical origins — we draw on standard academic and religious sources: the Encyclopaedia of Islam (Brill), the Encyclopaedia Iranica, the Encyclopaedia Judaica, UNESCO’s Intangible Cultural Heritage listings, the Coptic Synaxarion, Reingold & Dershowitz’s standard reference, and the official publications of religious authorities (Saudi Arabia’s Umm al-Qura, the Universal House of Justice for Bahá’í dates, the Ethiopian Orthodox Tewahedo Church’s published calendars). Quotations from religious scripture are attributed to standard editions (Sahih al-Bukhari, Sahih Muslim, the Hebrew Bible following the Masoretic text, the Qur’an, the Avesta, the Gathas). Where two sources disagree, we explain the disagreement rather than picking sides.
Contact and feedback
Found an error? Have a calendar we should add? Have an etymology, observance note, or historical detail we got wrong? Please get in touch — accurate timekeeping depends on community correction, and we treat every report seriously.