Wareki ⇄ Gregorian Year Converter (Japanese Eras)
Convert Gregorian years to Japanese era years (Meiji, Taishō, Shōwa, Heisei, Reiwa) and back, with era-change boundary years handled correctly.
🔒 Runs entirely in your browser. Your input and output are never sent to a server or stored — fully private.
Gregorian → Japanese era
Japanese era → Gregorian
The era changes mid-year, so the first/last year of an era overlaps with its neighbor (e.g. 1989 = Shōwa 64 until Jan 7, Heisei 1 from Jan 8). Click a result to copy.
About this tool
This Japanese era converter switches years between the Western calendar and Japan's era system (wareki) — Meiji, Taishō, Shōwa, Heisei and Reiwa — in both directions, right in your browser. Type a Gregorian year to get the era year (2026 is Reiwa 8), or pick an era and year to get the Western year. Transition years such as 1989 and 2019 correctly show both eras, and year 1 is displayed as gannen. Handy for filling in Japanese forms, reading official documents, or checking a birth year. Everything is computed locally — nothing is sent anywhere.
Frequently asked questions
Why do 1989 and 2019 show two eras?
Because the era changed mid-year. Shōwa ended on 7 January 1989 and Heisei began the next day, so 1989 is both Shōwa 64 and Heisei 1. Likewise Heisei ended on 30 April 2019 and Reiwa began on 1 May, so 2019 is Heisei 31 and Reiwa 1. Which name applies to a specific date depends on the month and day, so the tool shows both for those years.
What does gannen mean?
Gannen (元年) is the first year of an era — Japanese convention writes it with the character for "origin" instead of the number 1. So 2019 from 1 May onward is Reiwa gannen, not "Reiwa 1". From the second year on, ordinary numbers are used (Reiwa 2, Reiwa 3…). Official documents and forms follow this convention, and the tool displays it the same way.
Is my input sent anywhere?
No. The era boundaries are built into the page and the conversion is simple arithmetic done by JavaScript in your browser, so the years you type are never uploaded or stored. It even works offline once the page has loaded — useful when filling in paperwork away from a connection.