Taishō (大正) 15 — 1926

The same Western year

Meiji to Taishō and Taishō to Shōwa changed **on the same day**, so one calendar day belongs to both eras: 30 July 1912 is Meiji 45-07-30 and Taishō 1-07-30 at once. Shōwa to Heisei and Heisei to Reiwa changed **the next day**, so a single day separates them: Shōwa 64 ends on 7 January and Heisei 1 begins on the 8th.

Converting is one addition

Each era has a fixed number to add: 1867 for Meiji, 1911 for Taishō, 1925 for Shōwa, 1988 for Heisei, 2018 for Reiwa. Reiwa 6 is 6 + 2018 = 2024. The numbers differ not because the rule differs but because the eras began in different years — in every era, year one sits on the year it began.

The years either side

Other years of this era

The year of a change carries both names

1912 is Meiji 45 and Taishō 1; 1926 is Taishō 15 and Shōwa 1; 1989 is Shōwa 64 and Heisei 1; 2019 is Heisei 31 and Reiwa 1. In all four, neither label is wrong — only the date within the year decides which era applies.

How to read this

• Western year = era year + a fixed number (Meiji 1867, Taishō 1911, Shōwa 1925, Heisei 1988, Reiwa 2018).
• The first year is written 元年 (gannen), not 1.
• A year in which the era changed carries two era names; only the date settles it.
• Meiji and Taishō began on the same day as the previous era ended; Shōwa onward, the next day.