Japanese wareki converter

Why "year 1" is everywhere in Japanese forms

On a Japanese tax form, you'll see boxes for era + year (令和__年) instead of a four-digit Gregorian year. Year 1 of any era is called 元年 (gannen, literally "origin year") and starts on the day the emperor changed, not on January 1. So Reiwa 1 was only May 1 through December 31 of 2019 — eight months, not twelve. Forms designed before the era change still ask for it that way, and any conversion that treats Gregorian year as a proxy for era year quietly produces dates a year off.

The era-boundary years that break spreadsheets

Three Gregorian years contain a Reiwa-era boundary: 1912, 1926, 1989, and 2019. Each one is a footgun. 1989, for instance, is both Showa 64 (January 1 through January 7) and Heisei 1 (January 8 onwards). A lookup that maps year 1989 to "Heisei" gets the New Year holiday wrong by an entire era. The same trap fires in 2019, where everything before May 1 is Heisei and May 1 onwards is Reiwa. This converter always uses the actual date, never just the year.

Reiwa 8 = 2026 (and 5 ways to write it)

Reiwa 8 maps to most of 2026 (January 1 through December 31 — no boundary inside this year). The five common forms you'll see are:

1. 令和8年 — the full kanji form used on government forms.
2. Reiwa 8 — romanized, used in English-language Japanese contexts.
3. R8 — the single-letter abbreviation on driver's licenses and bank forms (M, T, S, H, R for Meiji, Taisho, Showa, Heisei, Reiwa respectively).
4. R8.04.15 — date format on official paperwork (era-abbr + year-of-era + month + day).
5. 令和8年4月15日 — full kanji date with 年/月/日 markers.