BlueprintLab ReferenceCalendars · Global

World calendars & era systems

Compare the same date across Gregorian, Japanese era, Minguo, Buddhist, Hijri, Persian, Hebrew, Chinese and other calendar systems.

ReferenceTools

Calendar dates can depend on observational or algorithmic conventions. Browser Intl output is a practical comparison, not a substitute for religious or legal authorities.

Calendar / eraSame dateUseNote
Gregorian
gregory
Current / civilThe most widely used civil calendar worldwide.
ISO 8601
iso8601
Current / civilGregorian-based representation for data interchange.
Japanese era
japanese
Current / civilEra-year system used in Japan.
Minguo / ROC
roc
Current / civilEra numbering widely used in Taiwan.
Thai Buddhist
buddhist
Current / civilBuddhist Era used in Thailand.
Hijri (Umm al-Qura)
islamic-umalqura
Current / civilSaudi Umm al-Qura variant of the Hijri calendar.
Hijri
islamic
TraditionalIslamic calendar; observed dates can vary by method.
Persian
persian
Current / civilSolar calendar important in Iran and Afghanistan.
Hebrew
hebrew
TraditionalUsed for Jewish religious and cultural observance.
Traditional Chinese
chinese
TraditionalUsed for traditional observances in Chinese communities.
Dangi / Korean traditional
dangi
HistoricalRelated to traditional Korean calendar/era conventions.
Indian National
indian
Current / civilIndian National Calendar (Saka).
Ethiopic
ethiopic
Current / civilCalendar used in Ethiopia.
Coptic
coptic
TraditionalUsed in the Coptic tradition.
Julian
julian
HistoricalImportant in historical and some ecclesiastical contexts.
Kōki / Japanese imperial year
koki
HistoricalHistorical Japanese era numbering; not a modern civil calendar.

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Verified: 2026-08-31. This page prioritizes primary standards and official registries. Time-sensitive items should be rechecked against the linked source.